1.

Question 60: A man wearing a bullet-proof vest stands still on roller skates. The total mass is 80 kg. A bullet of mass 20 grams is fired at 400 m/s. It is stopped by the vest and falls to the ground. What is then the velocity of the man ? Lakhmir Singh Physics Class 9

Answer»

0.1 m/sExplanation:Mass of the MAN = m1 = 80kg (GIVEN) Mass of bullet = m2 = 20 g = 0.02kg (Given) LET speed of the man be = v1 Speed of the bullet = v2 = 400 m/s (Given) Therefore, ACCORDING to the law of conservation of momentum -m1v1 = m2v2= 80 × v1 = 0.02 × 400v1 = 400 × 0.02/ 80 v1 = 0.1 Therefore, the velocity of the man is 0.1 m/s.



Discussion

No Comment Found

Related InterviewSolutions