4. You and another student push horizontally, but in exactly opposite directions, on a third child in a wagon. You exert a force of 75.0 N, the other student a force of 90.0 N to left, friction is 12.0 N, and the mass of the third child plus wagon is 23.0 kg.
a. What is the system of interest if the acceleration of Child and wagon is to be calculated?(1M)
b. Using free body diagram, Newtons laws, and appropriate motion equation determine the velocity of the child in the wagon if the scenario is applied for 5 seconds? (5M)
c. What happens to the child in the wagon if the wagon hits a curb and stops abruptly, and what newton law(or laws) does this scenario represent (3M)