The length of a telescope is 2.00 m and the focal length of the objective lens is 2.0 cm.What is the focal length of the eyepiece?
A)200 cm
B)202 cm
C)101 cm
D)2.0 cm
E)198 cm

Question

Quizplus · Accepted Answer

The focal length of the eyepiece can be found using the formula for the length of the telescope, $L = f_o + f_e$, where $L$ is the length of the telescope, $f_o$ is the focal length of the objective lens, and $f_e$ is the focal length of the eyepiece. Given $L = 2.00 m = 200 cm$ and $f_o = 2.0 cm$, solving for $f_e$ gives $f_e = L - f_o = 200 cm - 2 cm = 198 cm$.

The Length of a Telescope Is 2