1) A two-slit interference experiment uses laser light of wavelength 655 nm. The slits are 0.230 mm apart and 1.75 m from the screen on which the interference pattern appears. The intensity of the light at the central bright fringe is I(max) = 0.0520 W/m2. Find the intensity at a point on the screen 6.50 mm from the central bright fringe. 2) Find the distance on the screen from the central bright fringe to the nearest point where the intensity is I(max)/4.
Kindly include explanations as well, thank you!

they should be similar or the same

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.