An object is placed at a distance of 50 cm from a thin lens along the axis.If a real image forms at a distance of 40 cm from the lens,on the opposite side from the object,what is the focal length of the lens?

Question

Quizplus · Accepted Answer

The correct answer is A because the focal length of the lens is 22 cm. This can be calculated using the thin lens equation: 1/f = 1/do + 1/di, where f is the focal length, do is the object distance, and di is the image distance. In this case, do = -50 cm and di = 40 cm, so 1/f = 1/-50 cm + 1/40 cm = 1/22 cm. Therefore, f = 22 cm.

An Object Is Placed at a Distance of 50 Cm