The objective lens of the Yerkes telescope (the largest functioning refracting telescope in the world)has a focal length of 19.4 m.If its eyepiece has a focal length of 2.5 cm, what is the magnitude of its magnification?
A)7.8
B)13
C)130
D)780
E)cannot be calculated without knowing the length of the telescope

Question

Quizplus · Accepted Answer

The magnification of a telescope is calculated by dividing the focal length of the objective lens by the focal length of the eyepiece. Converting 2.5 cm to meters gives 0.025 m. Thus, magnification = 19.4 m / 0.025 m = 776, which rounds to 780.

The Objective Lens of the Yerkes Telescope (The Largest Functioning