Question

16. The velocity of a body of mass 10 kg increases form 4 m/sec to 8 m/sec When a force act

on it for 2 sec. find

(a) What is the momentum before the force act?

(b)What is the momentum after the force act?

(c) What is the momentum gain in momentum per sec.

(d)What is the value of force?​

Answer 1

Explanation:

a) momentum before= mv=10*4=40kgm/s

b) momentum after forces act = mv=10*8=80kgm/s

c) momentum gain =80-40/2=40/2=20

d) v=u+at

8= 4+a*2

a=2

f=ma=10*2=20 same as momentum gain by newton second law

Answer 2

Answer:

1. p=mv

p=10×4=40kgm/s

2.p=mv

p=10×8=80kgm/s

3.change in momentum =

(80-40)/2=20kgm/s

4.f=ma

f=10×(v-u)/t

10×(8-4)/2

10×2

20N