1
A body of mass 3 kg hits a wall at an angle of 60 and returns at the same angle. The impact time was 0.2 s. The force exerted on the wall is [figure]
- 150 3 N
- 50 3 N
- 100 N
- 75 3 N
Answer
(1) 150 3 N
Solution
The velocity makes 60 with the wall, so its component normal to the wall = v 60 .
Only the normal component reverses.
Change in momentum p = 2mv 60
= 2 3 10 32 = 30 3 kg m/s
F = p t = 30 30.2
= 150 3 N
Answer: (1)
AIPMT 2000