Question

A card sheet divided into squares is being viewed at a distance of 9 cm through a magnifying glass of focal length 10 cm held close to the eye . The magnification produced by it is ​

Answer 1

Answer:

a)

Area of each square, A=1mm2

u=−9, f=10

v1−u1=f1⇒v=−90cm

Magnification, m=v/u=−90/(−9)=10

Area of each square is 102×A=100mm2

(b)

The magnifying power of the lens is 

∣u∣d=925=2.8

(c)

No, magnification of an image by a lens and angular magnification (or magnifying power) of an optical instrument are two separate things. The latter is the ratio of the angular size of the object (which is equal to the angular size of the image even if the image is magnified) to the angular size of the object if placed at the near point (25 cm). Thus, magnification magnitude is ∣(v/u)∣ and magnifying power is (25/∣u∣). Only when the image is located at the near point ∣v∣=25cm, are the two quantities equal.

Answer 2

Answer:

مرحبا ماذا تفعل يا أخي

Explanation:

مرحبا ماذا تفعل اخي