A pendulum is raised to a certain height and released from point A, as shown in the image below. At its release, the pendulum is also given an initial
velocity of 14 m/s. Assuming that the effects of friction and air resistance
can be ignored, what will be the maximum height that the pendulum can
reach – that is, what is the height at point B? (Recall that g= 9.8 m/s2)

the answer is false

explanation:

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.