7.a railway truck A of a mass of 2000kg moves westwards with a velocity of 3m/s. It collides with a stationary truck B 1200kg, loaded with electronic equipment of mass 300kg. The two trucks combined after collision. Ignore the effects of friction. 7.1. Write down magnitude and direction of the 'reaction force' to the weight
of truck A.
(2)
7.2. Calculate the velocity of truck B after the collision.
(5)
7.3. Calculate the magnitude of the force that the truck A exert on truck B if
the collision lasts for 0,5 s.
(4)
8. The most common reasons for rear-end collisions are too shortfollowing a
distance, speeding and failing brakes. The sketch below represents one such​