Question

A small telescope has an objective lens of focal length 144 cm and an eye piece of focal length 6.0cm. what is the separation between the objective and the eye piece?

• A. 0.75 m
• B. 1.38 m
• C. 1.0 m
• D. 1.5 m

Answer 1

Answer: (D)

1.5 m

Answer 2

: The separation between the objective and the eye

Piece = Length of the telescope tube

$f = f_{0} + f_{e}$

Here,$f_{0} = 144cm = 1.44m$

$f_{e} = 6.0cm = 0.06m$

$\therefore f = 1.44 + 0.06 = 1.5m$