Question

A drone car with a mass of 2000 kg is traveling down the road at 21 m/s. It collides with another drone car half of the mass moving at -15 m/s. After the collision, the 2000 kg car is moving at -3.1 m/s. What is the speed of the other drone car after the collision?

Answer 1

`v_2 = 33.2m/s`

Step-by-step explanation:

Given

Before Collision

`m_1 = 2000kg`

`u_1 = 21m/s`

`m_2 = 1000kg`

`u_2 = -15m/s`

After Collision

`m_1 = 2000kg`

`v_1 = -3.1m/s`

`m_2 = 1000kg`

`v_2 = ???` ------ Required

As analyzed above;

To solve for v2, we simply make use of the law of conservation of momentum formula;

which states:

`m_1u_1 + m_2u_2 = m_1v_1 + m_2v_2`

Substitute values in the above formula

`2000 * 21 + 1000 * -15 = 2000 * -3.1 + 1000 * v_2`

`42000 - 15000 = -6200 + 1000v_2`

`27000 = -6200 + 1000v_2`

Collect Like Terms

`27000 + 6200 =1000v_2`

`33200 =1000v_2`

Divide through by 1000

`v_2 = (33200)/(1000)`

`v_2 = 33.2m/s`

Hence, the speed the other drone is 33.2m/s