1. Mary exerts an upward force of 40 N to hold a bag of groceries. Describe the “reaction” force…

1. Mary exerts an upward force of 40 N to
hold a bag of groceries. Describe the “reaction” force (Newton’s third law) by
stating (a) its magnitude, (b) its direction, (c) on what object it is exerted,
and (d) by what object it is exerted.

2. What force is needed to accelerate a
child on a sled (total mass 55 kg) at 1.4 m/s2?