Practice question · Multiple choice
A disk and a hoop of equal mass and radius roll down the same ramp, and the disk wins. Why does mass cancel while the shape does not?
Hints
- Write and put it into the rolling equation.
- See what survives the cancellation.
Show the answer
B. Because mass divides out and only its DISTRIBUTION remains
Why
Only survives: 1/2 for the disk, 1 for the hoop. Distribution, not amount, decides the race, which is why the result holds for any mass and any radius.
Practise Rotational Kinematics and Torque
The app has 10 more questions on this lesson, and keeps your place in the course. Physics I is free to start.