Ansel places an object 34.8 cm from a thin convex lens along the axis.If a real image forms at a distance of 13.2 cm from the lens,what is the focal length of the lens?
A)34.8 cm
B)21.3 cm
C)13.2 cm
D)9.57 cm
E)21.6 cm

Question

Quizplus · Accepted Answer

We can use the thin lens formula, 1/f = 1/do + 1/di, where f is the focal length, do is the object distance, and di is the image distance.

Plugging in the given values, we get:

1/f = 1/34.8 + 1/13.2

Simplifying this expression, we get:

1/f = (13.2 + 34.8)/(34.8 x 13.2)

1/f = 48/459.36

1/f = 0.1044

f = 9.57 cm

Therefore, the focal length of the lens is 9.57 cm. 
The correct choice is D.

Ansel Places an Object 34