Question

A rod of mass m and length l is hinged at one of its end A as shown in figure. A force F is applied at a distance x from A. The acceleration of centre of mass (1) varies with x as –

• A. A
• B. B
• C. C
• D. D

Answer 1

Answer: (B)

B

Answer 2

The rod will rotate about point A with angular acceleration:

a =$\frac{\tau}{I}$=$\frac{Fx}{\frac{ml^{2}}{3}}$=$\frac{3Fx}{ml^{2}}$

\ a =$\frac{l}{2}$ a =$\frac { 3 } { 2 }$ $\frac{Fx}{ml}$

or a µ x

i.e., a-x graph is a straight line passing through origin.