• question_answer A small laboratory telescope has an objective lens of focal length 140 cm and an eye-piece of focal length 6 cm. Then, separation between the objective and eye-piece is A)  140 cm            B)  24 cm C)  156 cm            D)  146 cm

Separation between objective and eye-piece is $L={{f}_{0}}+{{f}_{e}}$ $\therefore$ $L=140+6=146\,\,cm$