Question: 1. A brave but inadequate rugby player is being pushed backwards by an opposing player who is exerting a force of 800 N. The mass of the losing player plus equipment is 90.0kg and he is accelerating at 1.20 metre per second squared backward.
a: What is the force of friction between the losing players feet and the grass?
b. What force does the winning player exert on the ground to move forward if his mass plus equipment is 110 kg?
c: Draw a sketch of the situation showing the system of interest used to solve each part. For this situation draw a free body diagram and write the net force equation.
2. Suppose two children push horizontally, but in exactly opposite directions,on a third child in a wagon. The first child exerts a force of 75.0 N, the second a force of 90.0 N, friction is 12.0 N and the mass of the third child plus wagon is 23.0kg
a) What is the system of interest if the acceleration of the child in the wagon is to be calculated?
b) Draw a free body diagram, including forces acting on the system
c) calculate the acceleration
d) what would the acceleration be if friction were 15.0 N?
8) A system can have a nonzero velocity while the net external force on it ,is zero. Describe such a situation.