A box of mass m kg is placed on the rear side of an open truck accelerating at 4 ms-2 The coefficient of friction between the box and the surface below it is 0.4. The net acceleration of the box with respect to the truck is zero. The value of m is

Question

A box of mass m kg is placed on the rear side of an open truck accelerating at 4 ms-2 The coefficient of friction between the box and the surface below it is 0.4. The net acceleration of the box with respect to the truck is zero. The value of m is (A) 4 kg (B) 8 kg (C) 9.78 kg (D) It could be any value

Tardigrade Admin · Accepted Answer

Pseudo force on the block =m × 4 N (backward) Force of friction =0.4 × m × 10 N (forward) Equating, m × 4 =0.4 × m × 10 or 4 m=4 m Clearly the equation holds good for all values of m

Q. A box of mass $m k g$ is placed on the rear side of an open truck accelerating at $4 m s^{- 2}$ The coefficient of friction between the box and the surface below it is $0.4$ . The net acceleration of the box with respect to the truck is zero. The value of $m$ is

$4 k g$

$8 k g$

$9.78 k g$

It could be any value

Pseudo force on the block

$= m \times 4 N$ (backward)

Force of friction $= 0.4 \times m \times 10 N$ (forward)

Equating, $m \times 4 = 0.4 \times m \times 10$

or $4 m = 4 m$

Clearly the equation holds good for all values of $m$

Q. A box of mass mkg is placed on the rear side of an open truck accelerating at 4ms−2 The coefficient of friction between the box and the surface below it is 0.4. The net acceleration of the box with respect to the truck is zero. The value of m is

4kg

8kg

9.78kg