Why would it be incorrect to say that the bulb supplies 60 J of light energy energy each second

Explanation:

A 60W bulb , consumes electrical energy of 60 J per second but it does not give out all the energy in the form of light . Most of the energy consumed by it is wasted in the form of heat . Only a fraction of energy is converted into light energy .

Hence, it is wrong to say that bulb supplies 60 J of light energy each second .

if you already have the answer to (a), then just work out how many periods there are in 1 minute, and that's the answer to (c).

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.