A tennis player manages to hit a tennis ball with her racquet so that the ball passes over the net and lands in her opponent's court. A very strong wind is present. Consider the following forces: A downward force of gravity, a force by the "hit", and a force exerted by the air
Which of these forces is (are) acting on the tennis ball after it has left contact with the racquet and before it touches the ground?
a) 1 only b) 1 and 2 c) 2 and 3 d) 1 and 3 e) 1, 2 and 3

d) 1 and 3

Explanation:

When the ball leaves contact with the racquet , the force exerted by the racquet is no longer there . But the gravitational downward force and resistance force exerted by air will be present there . Hence except the force by the "hit" , all forces will be present there .

Hence option ( d ) is correct .

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.

i think the answer is a, hope this : )