Question

1. A 1700-kg car traveling east at 18 m/s collides with a moving 2500-kg truck.
After they collide, the two interlock and move together with a velocity of 30 m/s
west. What was the original velocity of the truck?

Answer 1

Answer:

The speed of the truck is 62.64 m/s towards west

Explanation:

As we know that there is no external force on the system of car and truck

so we can say that total momentum of the system must be conserved

so we will have

$m_1v_1 + m_2v_2 = (m_1 + m_2)v$

here we know that

$m_1 = 1700 kg$

$m_2 = 2500 kg$

$v_1 = 18 m/s$

$v_2 = ?$

$v = -30 m/s$

now we have

$1700(18) + 2500 v = (1700 + 2500)(-30)$

$v = 62.64 m/s$ Towards West