Question

If a solid sphere, disc and cylinder are allowed to roll down an inclined plane from the same height

• A. cylinder will reach the bottom first
• B. disc will reach the bottom first
• C. sphere will reach the bottom first
• D. all will reach the bottom at the same time

Answer 1

The correct option is C sphere will reach the bottom first

$I_{sphere}=\frac{2}{5}M{R}^2$

$\Rightarrow I_{cyclinder}=\frac{1}{2}M{R}^2$

$\Rightarrow I_{disk}=\frac{1}{2}M{R}^2$

$\because I_{sphere}$ is lesser than both $I_{cyclinder}$ and $I_{disk}$

$\therefore$ Sphere will reach the bottom first.

Hence, the answer is sphere will reach the bottom first.