# Rotational Motion and Torque Kit

Product Code: ME-1261

# Rotation and Torque Experiments

This set of rotational and torque experiments can be performed with the equipment from the Rotational Motion Plus Kit (ME-1261).

Grade Level: College • High School

Subject: Physics

### 01) Torsional Pendulum

The torsional pendulum consists of a torsion wire attached to a Rotary Motion Sensor with an object (a disk, a ring, or a rod with point masses) mounted on top of it. The period of oscillation is measured from a plot of the angular displacement versus time. To calculate the theoretical period, the rotational inertia is determined by measuring the dimensions of the object and the torsional spring constant is determined from the slope of a plot of force versus angular displacement.

### 02) Gravitational Torque

Students set up various systems to learn about gravitational torque and center of mass. They find the mass of an object, determine the mass of a meter stick, predict the location of a mass to balance an off-center meter stick, and locate the center of mass of an irregular object.

### 03) Exploring a Rotating System

Students construct and collect data with an experimental system to determine angular velocity, angular acceleration, applied torque, and the rotational inertia of the meter stick component.

### 04) Exploring Physical Pendulums

Students use a meter stick as a physical pendulum to explore the factors that affect the period and the mathematical properties of the physical pendulum period equation.

### 05) Centripetal, Tangential, and Angular Acceleration

A rod rotates in a horizontal plane, and is made to slow steadily to a stop. This setup is used to explore the different types of acceleration involved in this motion: centripetal, tangential, and angular acceleration.

### 06) Rotational Inertia

The purpose of this experiment is to find the rotational inertia of a ring and a disk experimentally and to verify that these values correspond to the calculated theoretical values.

### 07) Newton’s Second Law for Rotation

Newton’s Second Law for rotation: The resulting angular acceleration (α) of an object is directly proportional to the net torque (τ) on that object. The hanging mass applies a torque to the shaft of the Rotary Motion Sensor and the resulting angular acceleration of the rod and brass masses is investigated.

### 08) Rotational Kinetic Energy

This lab investigates the potential energies for a modified Atwood’s Machine, where a disk has been added to the Rotary Motion Sensor pulley.

### 09) Conservation of Angular Momentum

A non-rotating ring is dropped onto a rotating disk. The angular speed is measured immediately before the drop and after the ring stops sliding on the disk. The measurements are repeated with a non-rotating disk being dropped onto a rotating disk. For each situation, the initial angular momentum is compared to the final angular momentum. Initial and final kinetic energy are also calculated and compared.

### 10) Conservation of Energy of a Simple Pendulum

The purpose of this experiment is to use measurements of the motion of a simple pendulum to calculate and compare the different types of energy present in the system.

### 11) Physical Pendulum

A rod oscillates as a physical pendulum. The period is measured directly by the Rotary Motion Sensor, and the value is compared to the theoretical period calculated from the dimensions of the pendulum.

### 12) Large Amplitude Pendulum

This experiment explores the oscillatory motion of a physical pendulum for both small and large amplitudes. Waveforms are examined for angular displacement, velocity and acceleration, and the dependence of the period of a pendulum on the amplitude of oscillation is investigated.