when it reaches the maximum height, all the energy has now been converted into potential energy.when a ball is thrown straight upto into the air,all its initial kinetic energy converted into gravitational potential energy when it reaches its maximum height
Answer:
60 boxes
Explanation:
The work done by lifting a single box is equal to the force applied (the weight of the box) times the displacement of the box:

Power is related to the work done by the equation:

where W is the work done and t is the time. In this problem, we are told that the power used is P=60.0 W, while the time taken is t = 1 min = 60 s, so the total work done must be

Therefore, the number of boxes that she has to lift in order to use this power is the total work divided by the work done in lifting each box:

Answer:
0 km/h
Explanation:
Relative speed is the speed of a moving body with respect to another.
When two bodies move in the same direction then the relative speed is calculated as difference of their speeds.
In this case;
The two cars have the same speed. The relative speed will be;
72 km/h -72 km/h = 0 km/h