A 1 160.0 kg car traveling initially with a speed of 25.000 m/s in an easterly d
ID: 1290949 • Letter: A
Question
A 1 160.0 kg car traveling initially with a speed of 25.000 m/s in an easterly direction crashes into the back of a 9 200.0 kg truck moving in the same direction at 20.000 m/s. The velocity of the car right after the collision is 18.000 m/s to the east. (a) What is the velocity of the truck right after the collision? (Give your answer to five significant figures.) m/s east (b) What is the change in mechanical energy of the car-truck system in the collision? (c) Account for this change in mechanical energy.Explanation / Answer
a)
v2 = [(m2-m1)u2+2m1u1]/(m1+m2)
= 21.119 m/s
b)
Change in mechanical energy = change in kinetic enegy of the system
= [0.5m1u1^2+0.5m2v1^2] - [0.5m1u1^2+0.5m2v1^2]
= 37076 J
C)
Due to the collision some of their initial mechanical energy is converted into somany forms of energy like heat, sound. so there is change in mechanical energy.