PhysicsLAB: Test Scenario: Bicycle Experiment Scenario

Refer to the following information for the next fifteen questions.

In an experiment, students used a suspended 1.75-kg bicycle wheel, a motion detector, a slotted-mass hanger, and data analysis software to determine the wheel's moment of inertia.

They ran two trials with each of 6 different hanging masses. The mass hanger was always released from rest. The motion detector, which watched the falling mass-hanger, recorded a classic parabolic position vs time graph for accelerated motion.

Using data analysis they highlighted a section of the parabola and created a corresponding velocity-time graph. Its slope produced a value for the acceleration of the falling mass.

Since the masses were falling, the acceleration values were negative, supporting the experimental procedure that in each trial, the mass hanger was gaining speed in a negative direction.

Given below is a data table of their final experimental results.

mass (kg)	average a
0.05	0.362
0.06	0.438
0.07	0.515
0.08	0.593
0.09	0.671
0.1	0.752

Write the equation of motion for the falling mass-hanger.

Write the equation of motion for the rotating bicycle wheel.

Solving the previous two equations for 1/a yields the equation

Which variable should be placed on the x-axis and which on the y-axis when they graph their data?

Determine the (x, y) co-ordinates of the two grid points marked on the following graph of their experimental data.

What is the numerical value of the slope of their trend line (or line of best fit)?

Based on the line's slope, and the fact that the wheel had a radius of 0.28 meters, what was the bicycle wheel's moment of inertia?

Using the data from the group's last trial and the fact that a total of 1.6 meters of string was unwound off the wheel, how fast was the 0.1-kg mass-hanger moving downwards just as it reached the end of its descent?

How many revolutions did the wheel make while the mass-hanger descended?

What was the tension in the string during the last trial?

How much work was done on the bicycle wheel by the string as it was unwinding from its rim?

What was the wheel's final rotational kinetic energy at the end of the final trial?

What was the wheel's angular velocity when the 0.1-kg mass-hanger stopped falling and was jerked upwards?

What was the wheel's angular momentum just as the 0.1-kg mass-hanger reached the end of its downward journey?

What was the total kinetic energy in the system (rotational KE of the wheel plus linear KE of the mass-hanger) just as the 0.1-kg mass-hanger reached the end of the wrapped string and stopped falling?

What was the total potential energy just as the 0.1-kg mass-hanger was released from rest during the final trial?