THE PRACTICE STUDIO
Go slowly. Ask why. Make it yours.
PRACTICE / Rolling energy
Which rolling object reaches the greater speed?
A uniform solid cylinder and a thin hoop roll without slipping from rest down the same fixed incline through the same vertical drop. Their moments of inertia are ½mR² and mR² respectively.
What is the ratio of the cylinder’s final centre-of-mass speed to the hoop’s?
Organize the givens & assumptions
- Cylinder: I = ½mR²
- Hoop: I = mR²
- Equal drop from rest
Rigid bodies, enough static friction for pure rolling, no dissipative rolling resistance. Compare speeds after equal vertical drops.
- A
- B
- C
- D
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