Question

A 1560-kilogram truck moving with a speed of 28.0 m/s runs into the rear end of a 1070-kilogram stationary car. If the collision is completely inelastic, how much kinetic energy is lost in the collision?

Answer 1

Δ KE = 249158.6 kJ

Step-by-step explanation:

given data

Truck mass M = 1560 Kg

Truck initial speed, u = 28 m/s

mass of car m = 1070 Kg

initial speed of car u1 = 0 m/s

solution

first we get here final speed by using conservation of momentum that is express as

Mu = (M+m) V .......................1

put here value we get

1560 × 28 = (1560 + 1070 ) V

solve it we get

final speed V = 16.60 m/s

and

Change in kinetic energy will be here

Δ KE =
`(1)/(2) Mu^2 - (1)/(2)(M+m)V^2` .................2

put here value and we get

Δ KE =
`(1)/(2)* 1560* 28^2 - (1)/(2)* (1560 + 1070)* 16.60^2`

solve it we get

Δ KE = 249158.6 kJ