Question

a heavy vehicle moving with velocity 15m/s strikes an object of very small mass at rest head on elasticity velocity of object after collision is​

Answer 1

Answer:

Let the mass of vehicle be M

Velocity be V=15m/s

Mass of object be m

Velocity be v

V' is new velocity of vegicle

By applying conservation of momentum

MV = MV' + mv

M (V - V')=mv....(1)

By applying conservation of kinetic energy

By cancelling 1/2 from equation

MV*2=MV'*2+mv*2

M (V*2 - V'*2) = mv*2

M (V+V')(V - V') = mv*2 ....... (2)

By dividing 2 and 1

V+V' = v

V' = v - V.... (3)

By putting 3 in 1

v = 2MV/ M+m

M>>m

v = 2V

v = 2 ×15 =30m/s

Answer 2

Answer:

30 m/s

Explanation:

vehicle is heavy and object is very small so after collision velocity of object will not change significantly there fore velocity of vehicle after collision will be approximately 15 m/s so apply restitution coefficient

$e = 1 \: for \: elastic \: collision \\ e = \frac{v2 - v1}{u2 - u1 }$

v2 = find

V1 = 15 (velocity of vehicle after collision)

U2 = 15

u1 = 0

put values