You lay a mirror flat on the floor with one edge against a wall and aim a laser at the mirror. the ray reflects from the mirror and strikes the wall. the plane of the incident and reflected rays is perpendicular to the wall. the ray from the laser strikes the mirror 22.7 cm from the wall, and the reflected ray strikes the wall 35.5 cm above the mirror. find the angle of incidence of the laser ray on the mirror.

  About 32.6°

Explanation:

The tangent of the desired angle is the ratio of distance from the wall to height up the wall:

  tan(angle of incidence) = (22.7 cm)/(35.5 cm) ≈ 0.63944

  angle of incidence = arctan(0.63944) ≈ 32.6°

The angle of incidence is measured from the normal to the mirror.

force required to detach it is given by

charges are taken to be fundamental charge

now we have

so above is the minimum distance at which it will detach