Final answer:
The coefficient of restitution measures the elasticity of a collision. To find it, you need to calculate the relative velocity before and after the collision and divide the latter by the former. In this case, the coefficient of restitution between the truck and car is 0.481.
Step-by-step explanation:
The coefficient of restitution (e) is a measure of the elasticity of a collision. It is defined as the ratio of the relative velocity after the collision to the relative velocity before the collision.
The relative velocity before the collision can be found by subtracting the velocity of the car (2-Mg) from the velocity of the truck (7-Mg). So, relative velocity before the collision = 43 km/h - 16 km/h = 27 km/h.
The relative velocity after the collision is the velocity of the car (13 km/h) with respect to the truck. Since the car moves to the right relative to the truck, the relative velocity after the collision is positive.
To calculate the coefficient of restitution, we divide the relative velocity after the collision by the relative velocity before the collision:
e = (relative velocity after collision) / (relative velocity before collision)
Substituting the values, we get:
e = 13 km/h / 27 km/h = 0.481 (rounded to three decimal places).