Question
Physics Question on laws of motion
A gun applies a force F on a bullet which is given by F=(100−0.5105×t)N. The bullet emerges out with speed 400m/s−1. Then find out the impulse exerted till force on bullet becomes zero
A
0.2 N s
B
0.3 N s
C
0.1 N s
D
0.4 N s
Answer
0.1 N s
Explanation
Solution
F = (100 - 0.5 ? 10t)N Given F = 0 100 - 0.5 ? 10t = 0 100 = 0.5 ? 10t T = 2 ? 10 sec I = ∫F dt I = ∫02×10−3(100- 0.5 10 t)dt I=[100t−21052t2]02×10−3 I=[100×2×10−3−4105×4×10−6] I=[2×10−1−10−1] I=10−1=0.1 N-s