Question:
A block of mass 2 kg, moving with the initial
speed of 3 m/s comes to rest on a rough
horizontal surface after travelling a distance of
3 m, The magnitude of the frictional force is:
A block of mass 2 kg, moving with the initial
speed of 3 m/s comes to rest on a rough
horizontal surface after travelling a distance of
3 m, The magnitude of the frictional force is:
Options:
- 9 N
- 3 N
- 18 N
- 1 N
- 9 N
- 3 N
- 18 N
- 1 N
Correct Answer: B) 3 N
Explanation:
Using work-energy theorem, Friction force * distance = (1/2)*m*u^2 => F * 3 = (1/2)*2*9 = 9 => F = 3 N.
Using work-energy theorem, Friction force * distance = (1/2)*m*u^2 => F * 3 = (1/2)*2*9 = 9 => F = 3 N.