Confidently Integrate Computational Thinking into Any Lesson with Blockly
Introducing students to coding and computer-controlled outcomes is easier than ever before with Blockly coding. Included in SPARKvue 4 and Capstone 2, Blockly offers students a new world of experimental opportunities that focus on computational thinking and data visualization. Blockly’s visual coding environment is intuitively designed to facilitate the success of new coders, while strengthening the skills of more advanced learners.
Blockly’s colored coding blocks provide students with a visual method for developing strong coding foundations. The user-friendly design allows students to simply drag and connect coding blocks that correlate with syntactically correct coding elements such as variables, commands, and loops.
Blockly within SPARKvue and Capstone is compatible with all PASCO sensors and interfaces. When students combine PASCO sensors with Blockly, they are empowered to design and execute their very own sensor experiments. Students can create code that collects sensor measurements, reports data, or controls output devices such as the Smart Fan Accessory. As they execute their code, students can visualize their data using real-time graphical displays that assist with data visualization.
Real-World Coding Activities: Computational Thinking Meets Data Literacy
The integration of Blockly into SPARKvue and Capstone gives students unparalleled control over their experiments. While developing their code, students can press the Record button at any time to execute it and receive live feedback. Students can instantly monitor sensor measurements through live graphs and digits displays that support debugging throughout their code creation process. Once students have successfully coded their sensor parameters, they can collect data in real time, store it, and use it to inform future experiments.
With an unlimited amount of coding combinations, Blockly allows students to customize and create experimental designs, determine data outputs, and use those outputs to inform future decisions. Through the integration of coding and sensor-based technology, both SPARKvue and Capstone provide a platform for the exploration of phenomena through computational thinking and data visualization.
Sample Programming Activities
Entry Level Programming with the Wireless pH Sensor
The Wireless pH Sensor is the perfect tool for introducing young learners to pH and simple programming. In this activity, students use their knowledge of the pH scale and a Wireless pH Sensor to create code that runs along with their data collection. Using a simple set of coding blocks, students can instruct the sensor to identify a sample solution as neutral, basic, or acidic. As their code is executed, live data displays communicate the code’s effect in real time. A text display will correctly identify a solution’s pH. This simple activity gently introduces students to basic programming concepts, sensor measurement, and the pH scale to instill a foundational sense of confidence and understanding in STEM.
Entry Level Programming with the Wireless Temperature Sensor
For introductory lessons, students can learn to program a temperature display and a simple text output. The goal of this activity is for students to create a program that gives instructions to cool a liquid to below 15°C. Students can monitor their live temperature reading and a text output that is temperature-dependent. In this example, the text output reads “Add more ice!” when the water temperature is above 15°C, and “Great work!!” when the water temperature is less than or equal to 15°C. The Wireless Temperature Sensor should be placed in a cup containing room temperature water. Once students have developed their Blockly code, they can execute it using the Record button. Add the ice gradually to reduce the water temperature. A successful program will display a live temperature reading and the correct text when the temperature shifts above and below 15°C.
Advanced Level Programming: Thrust with Blockly and the Smart Fan Accessory
The patented Smart Fan Accessory adds versatility to any dynamics experiment. It features numerous control features when plugged into a Smart Cart. Students can control the fan’s thrust and direction from their devices. They can also set start and stop conditions that power the fan on or off when a particular measurement, such as position, reaches a set value. Students can easily determine a parameter and immediately observe its impact on the experimental outcome, which is a powerful component of active learning.
Students can control the fan’s thrust by programming calculations based on sensor measurements. In this example, a student commands the fan to maintain a thrust of -100*[Position]. This makes the fan blow harder as the cart moves down the track, causing the cart to reverse. When the fan senses a determined measurement, the student’s code is executed, producing a physical change in the experiment and altering data collection. Students can test their code’s effectiveness, make corrections, obtain live data, and complete graphical analysis before exporting their lab for grading. This user-friendly platform is an intuitive and time-efficient method for introducing students to computational thinking without straying from standards.
ISTE Standard: Computational Thinker (all ages)
5a Students formulate problem definitions suited for technology-assisted methods such as data analysis, abstract models and algorithmic thinking in exploring and finding solutions.
5b Students collect data or identify relevant data sets, use digital tools to analyze them, and represent data in various ways to facilitate problem-solving and decision-making.
5c Students break problems into component parts, extract key information, and develop descriptive models to understand complex systems or facilitate problem-solving.
5d Students understand how automation works and use algorithmic thinking to develop a sequence of steps to create and test automated solutions.
ISTE Standards Grades 3-5 (ages 8-11)
Data and Analysis
1B-DA-06 Organize and present collected data visually to highlight relationships and support a claim.
1B-DA-07 Use data to highlight or propose cause-and-effect relationships, predict outcomes, or communicate an idea.
Algorithms and Programming
1B-AP-08 Compare and refine multiple algorithms for the same task and determine which is the most appropriate.
1B-AP-09 Create programs that use variables to store and modify data.
1B-AP-10 Create programs that include sequences, events, loops, and conditionals.
1B-AP-13 Use an iterative process to plan the development of a program by including other perspectives and considering user preferences.
1B-AP-15 Test and debug (identify and fix errors) a program or algorithm to ensure it runs as intended.
ISTE Standards Grades 6-8 (ages 11-14)
2-CS-02 Design projects that combine hardware and software components to collect and exchange data.
Data and Analysis
2-DA-07 Represent data using multiple encoding schemes.
2-DA-08 Collect data using computational tools and transform the data to make it more useful and reliable.
2-DA-09 Refine computational models based on the data they have generated.
Algorithms and Programming
2-AP-10 Use flowcharts and/or pseudocode to address complex problems as algorithms.
2-AP-11 Create clearly named variables that represent different data types and perform operations on their values.
2-AP-12 Design and iteratively develop programs that combine control structure, including nested loops and compound conditionals.
2-AP-13 Decompose problems and subproblems into parts to facilitate the design, implementation, and review of programs.
NGSS Alignment (Grades 3-5)
Motion and Stability: Forces and Interactions
3-PS2-1 Plan and conduct an investigation to provide evidence of the effects of balanced and unbalanced forces on the motion of an object.
3-PS2-4 Define a simple design problem that can be solved by applying scientific ideas about magnets.
4-PS3-2 Make observations to provide evidence that energy can be transferred from place to place by sound, light, heat, and electric currents.
Waves and Their Applications in Technologies for Information Transfer
4-PS4-3 Generate and compare multiple solutions that use patterns to transfer information.
3-5-ETS1-2 Generate and compare multiple possible solutions to a problem based on how well each is likely to meet the criteria and constraints of the problem.
3-5-ETS1-3 Plan and carry out fair tests in which variables are controlled and failure points are considered to identify aspects of a model or prototype that can be improved.
NGSS Alignment (Grades 6-8)
Motion and Stability: Forces and Interactions
MS-PS2-3 Ask questions to determine cause and effect relationships of electric or magnetic interactions between two objects not in contact with each other.
MS-PS2-5 Conduct an investigation and evaluate the experimental design to provide evidence that fields exist between objects exerting forces on each other even though the objects are not in contact.
Waves and Their Applications in Technologies for Information Transfer
MS-PS4-3 Integrate qualitative scientific and technical information to support the claim that digitized signals are a more reliable way to encode and transmit information than analog signals.
MS-ETS1-3 Analyze data from tests to determine similarities and differences among several design solutions to identify the best characteristics of each that can be combined into a new solution to better meet the criteria for success.
MS-ETS1-4 Develop a model to generate data for iterative testing and modification of a proposed object, tool, or process such that an optimal design can be achieved.
Blockly is Compatible with All PASCO Sensors & Interfaces
Transpiration is an important concept in both biology and environmental science, especially in terms of the role it plays in the water cycle. As water evaporates from the stoma of leaves water is pulled up (due to hydrogen bonding) through the xylem from the roots which have drawn the water from the surrounding soil.
Because transpiration is essentially an invisible process, a potometer is used to measure the rate of water lost to the air. The advantages that sensor technology makes in many investigations in biology and environmental science are that it allows students to see the data in real-time while greatly improving the accuracy and significantly decreasing the time needed to capture data.
Setting up a classic potometer with a Wireless Pressure Sensor is one example of how integrating sensors can improve the data collection process. With the included Leur connectors and tubing, all you need is a plant sample and optional stand with clamps to complete the lab. Students can choose from any plants available, but three general guidelines help ensure success. Students should choose a plant with
a woody stem/branch that will fit snuggly into the tubing, making it less prone to crushing and easier to setup.
relatively soft cuticle leaves because they generally have higher rates of transpiration and good stomatal density.
high leaf surface area (either large leaves or lots of leaflets) per stem/branch.
Insert the plant stem into the tubing as shown, making sure there are no bubbles in the tubing and that you have a few centimeters of air between the sensor and water. This can take a few tries to get right, and having a sink or tub to submerse the tubing in will help. The cohesion and adhesion of the water along with a slight positive pressure created when connecting the sensor will keep water out of the sensor even if a stand is not available.
Data collection usually takes 5-10 minutes depending on the plant. For the control run (taken at room temp with ambient light) wait for a change of at least 5.0 kPa before stopping data collection. After the control run is complete, find the rate of transpiration in kPa/min using the curve fit tool and save this into a data table. Save the plants from each trial so the surface area can be calculated and the trial data normalized for comparison.
Calculating surface area (SA) can be done using the tried and true method with graph paper, but if you have cameras and computers available students can also use ImageJ— a free image analysis tool from the National Institute of Health. This is a powerful software and the basics are pretty easy to master. The steps for conducting area and size calculations in ImageJ can be found in this blog article or on this video. Although not part of the PASCO software suite, this is another tool that eliminates some repetitive work from the procedure and let students focus on the data and analysis that support learning.
When the SA is determined, add it to the data table in SPARKvue. A simple calculation provides the adjusted rate in kPa/Min/cm2. In subsequent trials, students can investigate the impact of environmental variables such as light intensity, humidity, temperature, and wind— or they can compare different species of plants.
You can download the sample data with the table formatted and calculations created. After students go through the procedure once they can easily iterate this setup to conduct their inquiry— where the true learning transpires!
We high school physics teachers tend to associate the right-hand rules with electromagnetism. As a student, my first encounter with a right-hand rule was when I was introduced to the magnetic field produced by the electric current in a long, straight wire: if you point the thumb of your right hand in the direction of the conventional current and imagine grasping the wire with your hand, your fingers wrap around the wire in a way that is analogous to the magnetic field that circulates around the wire.
I only later discovered that this same rule can be applied to rotational quantities such as angular velocity and angular momentum. The topic of rotation has become more important in AP physics when the program was updated from the older Physics B program. Strictly speaking, AP Physics 1 does not include the use of the right hand rule for rotation, but I have found that introducing it actually helps solidify student understanding of angular vectors.
Describing the direction of rotation as being clockwise or counterclockwise is helpful only if all parties involved have a common point of view, which is ideally along the axis of rotation. As with left and right, clockwise and counterclockwise depend on your point of view. This is why it is often preferable to describe translational motion in terms of north, south, east, west, up, and down, or with respect to a defined x-y-z coordinate system; directions can be communicated unambiguously, provided that everybody uses the same coordinate system.
It is precisely for this reason that the right hand rule can (and should) be used for rotational motion. Consider the hands of an analog clock. Assuming that the clock is a typical one, it will have hands that turn “clockwise” when viewed from the “usual” point of view, but if the clock had a transparent back and you were to view it from the back you would see the hands turning “counterclockwise!” The observed direction of rotation (clockwise or counterclockwise) depends on the observer’s point of view.
Instead of using clockwise and counterclockwise, we can describe the direction of rotation with a right hand rule: if you curl the fingers of your right hand around with the direction of the rotational motion, your thumb will point in the direction of rotation, which will be along the axis of rotation. Applying this to the above we find that when viewing a clock from the front, the rotation of the hands is three dimensionally into the clock (away from the observer), and when viewing a clock from the back side, the rotation of the hands is three dimensionally out of the clock (toward the observer). If two people view a transparent clock at the same time but one observes it from the front while the other observes it from the back (i.e. the clock is between the two people who are facing each other), they will disagree on which way the hands turn (clockwise or counterclockwise) but will agree on this direction if both use the right hand rule convention to describe the direction of the rotational motion – both observers will agree that it is directed toward the person viewing the back side of the clock.
When first learning about the right hand rule, students are often initially confused, with many students failing to grasp why such a rule is even useful in the first place. Before introducing the right hand rule I like to begin by holding an object such as a meter stick while standing at the front of the classroom. I then rotate the meter stick through its center so that the students claim that it is rotating “clockwise” when asked. Being careful to keep the rotational motion as constant as possible, I then walk to the back of the room. It’s important that the students see that at no point did I stop the rotation of the meter stick – it is still turning the same way as before, and yet at some point each student finds that they must turn around in order to continue to see it. Many students are astonished to see that the meter stick is now rotating counter clockwise from their (now reversed) point of view. This helps establish the need for a better way to describe rotation.
I then introduce the right hand rule and go through a couple of examples. Traditionally, this would have been the end of it, but last year I was able to take advantage of my newly acquired PASCO Smart Cart, which has a wireless 3-axis gyroscope (i.e. rotational sensor). The coordinate system is fixed with respect to the cart, and is printed on the cart itself, but I like to make this more visible by attaching cardboard cutout vectors onto the cart which make the axes more visible to the students while I hold the cart up for them to see. I then set up a projected display of the angular velocity of the cart along each axis simultaneously. I then ask the students how I must turn the cart in order to get a desired rotation of my choosing (i.e. ±x, ±y, and ±z).
I really like how the carts, along with the live display of the 3 angular velocity components make the admittedly abstract right hand rule so much more concrete. Seeing the display agree with our predictions makes it so much more real and is much, much better than me merely saying “trust me.” I have found that introducing and using this right hand rule with rotation has made using this same rule much more natural when using it to later relate the direction of current flow and the magnetic field.
Reposted from the NSTA Blog, original article can be found here.
The PASCO Wireless Spectrometer
Simply put, constructivism is a theory of knowledge that argues that humans generate knowledge and meaning from an interaction between their experiences and their ideas. So it follows that nothing is can be more constructivist than exploring the theoretical with real-time tools that measure the invisible. And the PASCO Wireless Spectrometeris just such a tool.
One of the most amazing things about the PASCO Wireless Spectrometer is that it does exactly what you would want it to do; show you the invisible with ease, simplicity, and leave behind a useful digital paper trail of graphs and charts. Although the main purpose of the PASCO Wireless Spectrometer was “specifically designed for introductory spectroscopy experiments” it actually goes farther than that. Much farther. Much much farther!
This trio of teachers, two from China and one from Mongolia have limited English speaking skills, but instantly understood the iPad app and PASCO Wireless Spectrometer. Seems that light is also a universal language.
The physics and electronics behind the PASCO Wireless Spectrometer are straight forward. The output is clear and obvious. And the mobility aspect is unprecedented. In other words, it does what it should how it should. Amazing enough on its own, but in true paradigm shifting fashion the PASCO Wireless Spectrometer presents the invisible world of visible light in the magical cartoon chart we’ve seen only in static textbooks for most of our lives. It’s as if the dinosaur skeletons in dusty museums suddenly came alive and reacted to the world.
Visible light, or the light our human eyes sense and convert to electrical impulses to our brains, only encompass a tiny fraction of the electromagnetic spectrum. Wavelengths between 390-700 nanometers, or from the short blue/violet waves to the longer orange/red ones with green and yellow in the middle. Infrared waves are just a little too long for us to see, and ultraviolet ones are a little too short. Even longer are radio waves, and even shorter are x-rays. The PASCO Wireless Spectrometer has a range of 380 to 950 nanometers meaning it can “see” a little into the ultraviolet and a lot into the infrared.
An ultraviolet light spikes the graph just outside the shortest wavelength we can see with our eyes.
Where this all comes together is that when the PASCO Wireless Spectrometer and various light sources are manipulated with our hands, the extended visible spectrum becomes something we can explore with the same cognitive dexterity as the microscope affords us in biology. When used in the classroom for demonstrations and explorations, the PASCO Wireless Spectrometer literally lets “humans generate knowledge and meaning from an interaction between their experiences and their ideas.” So yes, the PASCO Wireless Spectrometer is the epitome of constructivist theory into educational practice.
Although Isaac Newton is credited with discovering the inner workings of visible light back in the latter 1600s, the basic concept behind a rainbow was suggested by Roger Bacon 400 years earlier who in turn drew upon the works of Claudius Ptolemy a millennium before, and even Aristotle another 300 years before that.
As a quick digression here, the Newtonian physics behind the PASCO Wireless Spectrometer has roots much more than five times deeper into the past than Mr. Newton’s distance in time is from us right now. Sorry to go all Einstein on you, but the individual colors of visible light that Newton coaxed out of sunlight with only a glass triangle, and then reassembled with nothing more than a companion prism was like yesterday. Yet the attempts to explain the phenomena were first floated last week.
And now to think that within the palm of a student’s hand and the screen of their iPad is a gift of knowledge as great as the discovery itself. A stretch? Perhaps, but unless a scientific concept can be truly understood to the point one can make personal meaning out of the discovery, memorized facts are little more than coins used to buy grades.
Technically speaking, the PASCO Wireless Spectrometer is a battery operated spectrometer that uses Bluetooth wireless or a USB wire in order to communicate with a computing device running the necessary software. With its own built-in LED-boosted tungsten light source and three nanometer resolution, the PASCO Wireless Spectrometer provides an exceptional tool for traditional experimentation with pl
enty of room left over to inspect rarely explored specimens of light scattered throughout our lives.
The operation of PASCO’s unassuming black brick puts the power of spectrometry into the hands of grade school students and Ph.D. candidates alike. While maybe not the most durable block in the scientific toy box, the PASCO Wireless Spectrometer does offer a level of simplicity (when desired) as easy to use as glass prism and sunlight. Of course you can do much more with the PASCO Wireless Spectrometer, but you don’t have to in order to get your money’s worth. This spectrometer does so much so well so easily that it literally rewrites lesson plans just by walking into the classroom.
On a higher level, the PASCO Wireless Spectrometer can be used in chemical experiments of intensity, absorbance, transmittance and fluorescence all while using a device that, according to PASCO, has light pass through the solution and a diffraction grating and then a CCD array detects the light for collection and analysis. Sounds simple enough just like a digital prism should. Except this one gives about nine hours of service per battery charge.
In the off chance that the battery fails, it is user-replaceable. in the off chance the light burns out, it is user-replaceable. And in the likely chance that liquid from a cuvette spills into the holder, a drain hole limits the damage, and cleaning the holder is user-serviceable with a cotton swab and deionized water.
A portable studio light is used to provide a background of predictable photons in order to explore the absorbance properties of various types of matter including sunglasses, polarizers, fabric, and theater lighting filters.
The PASCO Wireless Spectrometer must interface with a computer or tablet. Both Mac and Windows are supported as is iOS and Android.
PASCO also suggests using the Wireless Spectrometer for the following popular labs:
Absorbance and transmittance spectra
Beer’s Law: concentration and absorbance
Photosynthesis with DPIP
Absorption spectra of plant pigments
Concentration of proteins in solution
Rate of enzyme-catalyzed reactions
Growth of cell cultures
Light intensity across the visible spectrum
Emission spectra of light sources
Match known spectra with references
And PASCO also provides several sample labs for plug-and-play directly into the chemistry classroom. But the really exciting plug-and-play option is the accessory fiber optic probe. With no more effort than sliding a faux cuvette into the receiving slot on the spectrometer, a meter-long fiber cord moves a directional sensor out into the wild where it can capture photons from all kinds critters. Some of my favorite animals include UV lights, filtered lightbulbs, various school lighting sources, sunlight though sunglasses, polarizers, and pretty much any LED flashlight I can find, especially the really good ones.
Although the screen output from the PASCO Wireless Spectrometer’s software is a graphical representation of a physical property, it takes almost no mental gymnastics to understand the changes to the graph once your mind is oriented to the display. The color-coded background and gesture-ready scaling provides an exceptionally smooth relationship with the data to the point all the hardware and software disappear leaving only the experiment and the results. And in my book, that kind of invisibility is the true measure of success with a teaching product.
When teaching the next generation about the important discoveries of the past generations, we have an obligation to use the most powerful educational tools possible. The PASCO Wireless Spectrometer is truly 100% pure constructivism-in-a-box. It turns experiences and ideas into personal meaning. Battery included and no wires necessary.
CAPSTONE 2.0 is out now! Free Upgrade for Capstone 1.x users!
Updated with new tools! Designed specifically to collect, display and analyze data in physics and engineering labs.
Features for Capstone 2.0!
Helps Students Develop Computational Thinking Skills
Physics educators want more experimental control and programming access to all PASCO interfaces and sensors. Students need tools to develop creative programing and problem solving skills in science. Blockly coding has been built into Capstone 2, giving teachers and students the tools they need to develop these skills.
With PASCO Capstone In Your Lab:
Apply coding concepts to your labs
Create new sampling conditions
Design Sense and Control experiments
Create whatever experiment you or your students can dream up!
Trials Table – Coming in 2020!
You never take only one run in science. You take multiple runs and calculate averages. Next, you vary a parameter while holding the other constant; again, taking more runs and calculating averages. Most software data tables don’t actually allow this to be done easily.
The Capstone Trials Table was created for how data is collected in the science lab and allows for the kind of analysis students need to perform.
Organize your data to easily define physical relationships
Plot derived values
Using the simple pendulum lab as an example, students will time a simple pendulum under various conditions. They will vary the mass, length, and starting angle. The Capstone Trials Table allows you to vary and keep track of experimental parameters between trials and runs taken in each trial. You can also keep track of statistics for averaged runs and experimental error.
Scientists always take multiple runs and calculate averages. Next, they vary a parameter while holding the others constant; again, taking more runs and calculating averages. Most software data tables don’t support this and require data export and processing… until Capstone 2.
The Capstone Trials Table was created to reflect how data is collected in science labs. It supports the analysis students need to develop critical thinking skills and interpret the data.
With Capstone students can:
Organize data to easily define variable relationships
Track multiple variables
Average runs within a trial group
Plot derived values (such as an average of runs vs. a group parameter)
For example, in the Simple Pendulum lab, students time a pendulum under different conditions by varying the mass, length, and starting angle. The Capstone Trials Table allows you to manipulate variables and track experimental data between trials and runs. You can also keep track of statistics for averaged runs and experimental error.
Graph Pop-Up Tools
Now, whenever tools are activated, the most common actions will be easily accessible on the graph. The pop-up tools allow for easy access to tool features and options.
Reinforce circuit concepts and tackle student misconceptions using circuit visualization. Combine real-world circuits with simulations, animation, and live measurements. Drag components from the components list, then rotate them and connect pieces together by drawing wires.
With the Circuits Emulation tool in Capstone 2, you can:
Construct and modify circuits
Show conventional current and electron flow animation
Animate circuits with live sensor data
Drag components out from the components list. Rotate components and connect pieces together by drawing wires.
Capstone includes a very powerful video analysis feature which can be used for comprehensive analysis of moving objects as well as to improve understanding. Short video clips from your smartphone can be easily imported and analysed with a range of tools. The movement of objects with a high contrast to a uniform background can be automatically tracked by the software.
A ball will be thrown in a parabolic arc and various tools will be used to analyze the motion. Note that the vertical and horizontal axes have been marked and a distance of 4.00 m has been measured. This will enable the software to translate from pixels to m:
As part of the analysis, the position of the ball in each frame is marked and the result is as shown below:
It is now possible to have the software generate various graphs such as position vs time and velocity vs time.
A graph of vertical position vs time is as shown below:
A graph of horizontal position vs time yields the following:
A graph of the vertical component of velocity vs time yields the following result:
Capstone also includes tools that improve understanding. For example, in the screen below, the vertical and horizontal components of velocity are shown for the ball as it flies through the air.
To make the display less cluttered and less confusing it is possible to mark the vectors at an interval other than every frame. Below the vectors are shown every third frame:
It is also possible to have a single vertical vector and a single horizontal vector appear and move with the ball as it goes through the air.
It is also possible to show the acceleration vector as shown below:
The fact that a few vectors do not point directly down is likely due to minor errors made when marking the position of the ball in various frames with a mouse.
Your students will be amazed at how the PASCO strobe light instantly and dramatically freezes the motion of a vibrating string – appearing as if it’s stopped in time.
By slightly adjusting the strobe’s frequency, the string’s frozen wave will appear as if it is moving slowly forwards or backwards. This wave freezing demonstration approaches absolute zero on the ‘cool’ factor scale!
It was the shot heard across Canada. There were a lot of factors that made Kawhi’s buzzer beating basket so remarkable. Aside from there being no time left on the clock and the weight of a sport’s nation on his shoulders, Kawhi had to overcome the backward momentum that is inherent in a ‘fadeaway’. The purpose of a fadeway is to create space between the shooter and defender(s), which was a necessity for Kawhi as there were several seriously tall 76ers trying to screen his shot.
Over-coming the fadeway’s backwards momentum is no easy feat as it requires players to quickly calibrate in their minds the additional force that is required to successfully sink a basket, which for most mere mortals is not intuitive. The shot is so challenging that only a handful of NBA basketball players have been able to reliably make this shot; and we’re talking the great players such as Michael Jordan, Lebron James, Kobe Bryant and of course Kawhi Leonard.
The video below provides an extreme example of backwards momentum with a soccer ball shot from the back of a truck
Investigating Kawhi Leonard’s shot in the lab
In addition to backwards momentum there were many additional physical factors at play such as the angle of the shot and gravity. Investigating all these forces in a single activity would not be practical. Fortunately most of these forces can be isolated and explored in the lab using PASCO sensors, software and/or equipment.
Exploring The fadeaway’s negative momentum using PASCO
PASCO offers an intriguing and affordable solution to model the dramatic effect of a fadeaway’s negative momentum on projectile distance. PASCO’s mini launcher will consistently launch projectile balls the same horizontal distance for a set angle, assuming that the launcher is stationary. If however, the launcher is placed on PASCO’s frictionless cart, the force of pulling the trigger will cause the cart to move backwards at a velocity that can be measured using the motion sensor. Students will be surprised to see that even though the cart travels just a few centimeters, the overall projectile distance is significantly reduced. This can be a very simple demonstration or an in-depth quantitative analysis that factors in the projectiles initial angle and velocity, the time of flight and even the k-constant of the spring.
Other Forces Affecting a Basketball Shot
Momentum and Explosions
When a basketball player takes a jump shot (as with a fadeway), the player and the ball could be viewed as 2-object linear system if you ignore other outside forces such as gravity. What’s interesting, and perhaps not apparent to many students, is that the basketball will exert an equivalent force to the player as the player is exerting on the basketball (Newton’s 3rd Law). Of course because of the very significant inertia (mass) difference between the two objects, the basketball will accelerate at a much fast rate than the player. The player however will experience some acceleration in the opposite direction to that of the basketball.
Using Smart Carts to explore Momentum and Explosions (Free Lab)
The Wireless Smart Carts are equipped with an exploding plunger. Multiple 250g bars can be added to one cart to skew the masses. The velocities of both carts are measured using the cart’s internal position sensors enabling students to determine that momentum is conserved in a linear exploding system.
The player’s force on the basketball will be equal to the opposing force of the basketball onto the player. Of course most students will consider this a ridiculous proposition until they prove this for themselves.
Using Smart Carts to explore Newton’s Third Law
There are several ways the carts can be used. The simplest activity is for two students to have a tug-of-war using the internal force sensors of two Smart Carts and an elastic band as depicted in the image. The equal but opposite forces will be confirmed, however in relation to a basketball player taking a shot, it has some shortcomings as the forces are pulling as oppose to pushing.
An equally simple activity, and one more relevant to the basketball shot scenario, is to collide two Smart Carts (with magnetic bumpers attached to their force sensors). As both carts have equivalent masses, students may not be surprised to see the impact forces are identical. However, what will probably surprise your students, are the force measurements that occur during a collision when one cart is weighed down with one or more 250g masses. Using their intuition, most students will speculate that one of the carts will experience a much greater force than the other. Of course, Newton’s 3rd Law will triumph and the forces will be identical.
What goes up must come down. This is true of course for all earth bound objects (including basketballs) due to the ever present force of gravity. Without gravity the trajectory of a basketball player’s shot would be straight to the ceiling of the arena, where most of the fans would be viewing the game.
Exploring the accelerating force of gravity using the Motion sensor
PASCO offers several technologies and techniques for measuring gravity including the Wireless Smart Gate and Picket Fence and the new Freefall apparatus. Both of these techniques are accurate and precise means to measure gravity. A third technique and one more appropriate for relating to a basketball shot is to measure the position of a vertically tossed ball and then have the software derive an acceleration graph from this data. Statistics, including the Mean of the acceleration plot can be calculated by the software for the period when the ball was in freefall as shown in the graph.