Question

derive an expression for the total magnification of a compound microscope​

Answer 1

otal magnification of a compound microscope= M = me x m0

me and mo are the magnifying power of objective lens and eye lens. 

or M = L/fo ( 1 + D/fe)

L = length of telescope

fo = focal length of objective

fe= focal length of eye lens

The focal length of both the lenses are kept short to keep the magnifying power big. 

Answer 2

$<b>____________♦♦♥♦♦____________$

$\huge\mathfrak\purple{\:\:\:\:\:\:\:\:hello\:\:\:mate}$

$<b>____________♦♦♥♦♦____________$
$\tt{\pink{\huge{here\:is\:your\:answer}}}$
$<b>____________♦♦♥♦♦____________$

$\huge\mathfrak\purple{simple\:microscope}$

(See fig 1st)
It is used for observing magnified images of objects. It is consists of a converging lens of small focal length.

Magnifying Power

(i) When final image is formed at least distance of distinct vision (D), then M=1+d/f

where, f= focal length of the lens.

(ii) When final image is formed at infinity, then M = D/f

$\huge\mathfrak\purple{Compound\:Microscope}$

(See fig. 2nd)
It is a combination of two convex lenses called objective lens and eye piece separated by a distance. Both lenses are of small focal lengths but fo < fe, where fo and feare focal lengths of objective lens and eye piece respectively

Magnifying Power

M = vo / uo {1 + (D/fo)

Where vo= distance of image, formed by objective lens and
uo = distance of object from the objective

(ii) When final image is formed at infinity, then
M = vo/uo . D/fe

$\huge\mathfrak\purple{Astronomical\:microscope}$

(See fig. 3rd)
It is also a combination of two lenses, called objective lens and eye piece, separated by a distance. It is used for observing distinct images of heavenly bodies like stars, planets etc

Magnifying Power

(i) When final image is formed at least distance of distinct vision (D), then M = fo/fe {1+ (D/fe)} where foand fe are focal lengths of objective and eyepiece respectively.

Length of the telescope (L) = (fo + ue)

where, ue = distance of object from the eyepiece.

(ii) When final image is formed at infinity, then M = fo/fe

Length of the telescope (L) = fo + fe

For large magnifying power of a telescope fo should be large and feshould be small.

For large magnifying power of a microscope; fo < fe should be small.

$<b>____________♦♦☺♦♦____________$

$\sf\purple{By-\:\:\:RAKESH\:\:PATEL}$

$\mathbb{\red{\huge{\:\:\:\:\:THANK\: YOU}}}$
$<b>________▶▶▶⭐⭐⭐◀◀◀________$