Do the following exercises to study the refraction between energy, work and power and identify the best alternative.
Explain whether or not you do work.

You push a wall.
You hold a book 2 meters high. You move a cart forward.

What is the orbital period of a spacecraft in a low orbit near the surface of mars? the radius of mars is 3.4×106m.

During the experiment if you could triple the breakaway magnetic force with all other quantities left unchanged, what is the new value for the critical velocity if it was v0 (initial velocity), initially? (b) now if you halved the radius with all other quantities left unchanged, what is the new critical velocity if it was v0 (initial velocity), initially? (c) if during the experiment, critical velocity quadrupled with all other quantities left unchanged, what is the new breakaway force if its magnitude was initially f0,?

At what time will the interfering waves have an amplitudeof zero?