If an astronomical telescope has objective and eye-piece focal lengths of $200 \; cm$ and $4 \; cm$ respectively,then the magnifying power of the telescope for normal vision is:

$A$ Galileo telescope has an objective of focal length $100 \, cm$ and magnifying power $50$. The distance between the two lenses in normal adjustment will be....$cm$

Focal length of objective and eye piece of telescope are $200 \; cm$ and $4 \; cm$ respectively. What is the length of telescope for normal adjustment (in $; cm$)?

In an astronomical telescope,the focal lengths of the objective lens and the eyepiece are $150 \, cm$ and $6 \, cm$ respectively. In the case where the final image is formed at the least distance of distinct vision,the magnifying power is:

This question has Statement-$1$ and Statement-$2$. Of the four choices given after the Statements,choose the one that best describes the two Statements.
Statement-$1$: Very large size telescopes are reflecting telescopes instead of refracting telescopes.
Statement-$2$: It is easier to provide mechanical support to large size mirrors than large size lenses.

In an astronomical telescope in normal adjustment,a straight black line of length $L$ is drawn on the objective lens. The eyepiece forms a real image of this line. The length of this image is $l$. The magnification of the telescope is