Determine the impulse of a car with a mass of 1.5 t, moving at a speed of 20 m / s in the frame of reference

Determine the impulse of a car with a mass of 1.5 t, moving at a speed of 20 m / s in the frame of reference, associated: a) with a car stationary relative to the Earth; b) with a car moving in the same direction at the same speed; c) with a car moving at the same speed, but in the opposite direction

Given:
m = 1.5 tons = 1500 kg – vehicle weight;
v = 20 m / s – vehicle speed.
It is required to find the momentum of the car:
a) in the reporting system associated with a stationary vehicle;
b) in a reporting system associated with a vehicle moving at the same speed in the same direction;
c) in a reporting system associated with a vehicle moving at the same speed in the opposite direction.
a) the vehicle speed in the reporting system associated with a stationary vehicle is equal to the vehicle speed v. Then the impulse is:
p = m * v = 1500 * 20 = 30,000 kg * m / s.
b) since the second car is moving at the same speed in the same direction, the speed of the first car in this reporting system is 0, then:
P = m * 0 = 1500 * 0 = 0
c) since the second car is moving at the same speed, but in the opposite direction, the speed of the first car in this reporting system is 2 * v, then the impulse is:
P = m * 2 * v = 1500 * 2 * 20 = 60,000 kg * m / s.
Answer: in case a the impulse is 30,000 kg * m / s, in case b the impulse is 0, in case c the impulse is 60,000 kg * m / s.