A large truck of mass 4M is traveling at a speed of V when it collides with a small car of mass M that is at rest. The truck and car stick t

Question

A large truck of mass 4M is traveling at a speed of V when it collides with a small car of mass M that is at rest. The truck and car stick together after the collision. When the truck and car stuck together after the collision, the speed of the center of mass of the truck-car system is Vf. If the truck and car have an elastic collision, the speed of the center of mass of the truck-car system is Vf2. Which of the following expressions for Vf2 must be true?

a. 4/5 V
b. 1/5 V
c. V
d. 5/4 V
e. 5V

in progress 0
Vân Khánh 5 years 2021-08-15T03:07:03+00:00 1 Answers 186 views 0

Answers ( )

  1. Delwyn
    0
    2021-08-15T03:08:56+00:00
    Reply

    Answer: (a)

    Explanation:

    Given

    Mass of large truck is 4M with velocity V

    Mass of small car is M which is at rest

    After the collision car and truck stick together

    Conserving momentum

    \Rightarrow 4MV+M(0)=5M\times V_f\\\\\Rightarrow V_f=\dfrac{4}{5}V

    For elastic collision, the velocity of the center of mass remains the same as the momentum is conserved and there is no acceleration involved.

    So, for elastic collision velocity V_f_2=\frac{4}{5}V

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )