An object,located 96 cm from a concave lens,forms an image 34 cm from the lens on the same side as the object.What is the focal length of the lens?

Question

Quizplus · Accepted Answer

Using the lens formula,
1/f = 1/v - 1/u,
where f is the focal length, v is the image distance, and u is the object distance.

Plugging in the values given in the problem:
u = -96 cm (since the object is on the same side as the image)
v = -34 cm (the negative sign indicates a virtual image)
1/f = 1/-34 - 1/-96
1/f = -0.0294
f = -34.0 cm

Therefore, the focal length of the concave lens is -53 cm, which is choice C.

An Object,located 96 Cm from a Concave Lens,forms an Image