An astronomical telescope is made with lenses of focal lengths 80.0 and 2.00 cm.What is the barrel length on this telescope?
A) 80.0 cm
B) 82.0 cm
C) 78.0 cm
D) 105 cm
E) 127 cm

Question

Quizplus · Accepted Answer

The barrel length of a telescope is given by the sum of the focal lengths of its lenses. Therefore, the barrel length of this telescope is:
80.0 cm + 2.00 cm = 82.0 cm
Thus, the correct choice is B.

An Astronomical Telescope Is Made with Lenses of Focal Lengths