You shine a laser beam through a grating with a known number of slits per millimeter and observe a pattern on a screen. Then you cover half of the grating with nontransparent material. What will you see

(a) There will be half as many bright fringes on the screen.(b) The bright fringes will be twice as close.(c) The bright fringes will be two times farther apart.(d) The location of the fringes will not change, but they will be a little bit wider and less bright.

d) The location of the fringes will not change, but they will be a little bit wider and less bright.

Explanation:

When one blocks half of the grating slits, the intensity of the interacting light is reduced, which reduces the brightness of the light. The angle of interference on the screen increases, thus is due to the reduced intensity of the light beams which makes the pattern become wider.

since you're a real machine, your ama is always less than your ima, because you can never totally eliminate friction.