ExamBro
ExamBro
JEE Advanced · Physics · 8. Rotational Motion

Statement 1 Two cylinders, one hollow (metal) and the other solid (wood) with the same mass and identical dimensions are simultaneously allowed to roll without slipping down an inclined plane from the same height. The hollow cylinder will reach the bottom of the inclined plane first.
and Statement 2 By the principle of conservation of energy, the total kinetic energies of both the cylinders are identical when they reach the bottom of the incline.

  1. A Statement 1 is true, Statement 2 is true, Statement 2 is a correct explanation for Statement 1.
  2. B Statement 1 is true, Statement 2 is true, Statement 2 is not a correct explanation for Statement 1.
  3. C Statement 1 is true, Statement 2 is false.
  4. D Statement 1 is false, Statement 2 is true
Verified Solution

Answer & Solution

Correct Answer

(D) Statement 1 is false, Statement 2 is true

Step-by-step Solution

Detailed explanation

In case of pure rolling on inclined plane,
\(a=\frac{g \sin \theta}{1+I / m R^2} \)
\( I_{\text {solid }} < I_{\text {hollow }} \)
\( \therefore a_{\text {solid }}>a_{\text {hollow}}\)
\(\therefore\) solid cylinder will reach the bottom first.
Further, in case of pure rolling on stationary ground, work done by friction is zero. Therefore, mechanical energy of both the cylinders will remain constant.
\(\therefore(\mathrm{KE})_{\text {Hollow}}=(\mathrm{KE})_{\text {solid}}=\) \(\text {decrease in } \mathrm{PE}=m g h\)
\(\therefore \text {correct option is }(\mathrm{d})\)
Same subject
Explore more questions on app
From JEE Advanced
Explore more questions on app