Q.
A circular disc with a groove along its diameter is placed horizontally. A block of mass $1kg$ is placed as shown. The co-efficient of friction between the block and all surfaces of groove in contact is $\mu = 2/5$. The disc has an acceleration of $25\ m/s^{2}$. Find the acceleration of the block with respect to disc
A) $10\ m/s^{2}$
B) $5\ m/s^{2}$
C) $20\ m/s^{2}$
D) $1\ m/s^{2}$
Explanation
(a) Making FBD of block with respect to disc
Let $A$ be the acceleration of block with respect to disc
[image:5_image222.emf]
$N_{1} = mg$
$N_{2} = m\ a\sin\theta$
$A = \frac{m\ a\cos\theta - \mu N_{2} - \mu N_{1}}{m} = 10m/s^{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.