A 20 ft3 rigid tank initially contains saturated refrigerant-134a vapor at 160 psia. As a result of heat transfer from the refrigerant, the temperature drops by 55 ?F. Determine (a) the nal pressure, (b) the amount (mass) of refrigerant that has condensate, and (c) the heat transfer.

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.

0.93xc=0.93x3x10^8m/s

2.54cm is 1 inch

360seconds i 1 hr