Answer:
Explanation:
mass of car, m1 = 1170 kg
mass of truck, m2 = 9800 kg
initial velocity of car, u1 = 25 m/s
initial velocity of truck, u2 = 20 m/s
final velocity of car, v1 = 18 m/s
Let the final velocity of truck is v2.
(a) Use the conservation of momentum
m1 x u1 + m2 x u2 + m1 x v1 + m2 x v2
1170 x 25 + 9800 x 20 = 1170 x 18 + 9800 x v2
29250 + 196000 = 21060 + 9800 v2
v2 = 20.84 m/s
(b) Total kinetic energy before collision,
Ki = 0.5 x 1170 x 25 x 25 + 0.5 x 9800 x 20 x 20
Ki = 365625 + 1960000 = 2325625 J
Total final kinetic energy
Kf = 0.5 x 1170 x 18 x 18 + 0.5 x 9800 x 20.84 x 20.84
Kf = 189540 + 2128097.44
Kf = 2317637.44 J
Change in energy = 2325625 - 2317637.44 = 7987.56 J
(c) It is due to the heat energy
