Question

A 1900 kg truck moving 15 m/s north collides with a 1000 kg car traveling south at 30 m/s. The cars stick together after the collision. Calculate the final velocity after the collision.

A. 7.5 m/s south
B. 15 m/s south
C. 22.5 m/s south
D. 15 m/s north

Answer 1

The final velocity after the collision between the truck and car is 15 m/s north.

Step-by-step explanation:

In this question, we have a collision between a truck and a car. The truck has a mass of 1900 kg and is moving north at 15 m/s. The car has a mass of 1000 kg and is moving south at 30 m/s. When the collision occurs, the two cars stick together. To find the final velocity after the collision, we can use the principle of conservation of momentum.

The initial momentum of the truck is given by:

momentum = mass * velocity

momentum of truck = 1900 kg * 15 m/s = 28500 kg*m/s

The initial momentum of the car is given by:

momentum of car = 1000 kg * (-30 m/s) = -30000 kg*m/s (since the car is moving in the opposite direction)

The total initial momentum is the sum of the momenta of the two cars:

total initial momentum = 28500 kg*m/s + (-30000 kg*m/s) = -1500 kg*m/s

Since momentum is conserved, the final momentum after the collision is also -1500 kg*m/s. Since the two cars stick together, they are moving in the same direction. Therefore, the final velocity will be in the same direction as the initial velocity of the truck, which is north. Hence, the correct answer is 15 m/s north (D).