Question

A rod of length 10 cm lies along the principal axis of a concave mirror of focal length 10 ’em in such a way that its end closer to the pole is 20 cm away from the mirror. The length of the image is
(a) 10 cm
(b) 15 cm
(c) 2.5 cm
(d) 5 cm

Answer 1

Answer:

d = 5 cm

Explanation:

pls like the answer

Answer 2

Answer:

ans is 5cm.

there are two cases.

in which the first end is at 20cm from the pole of mirror.

use,

1/V+1/U=1/F

here u=-20cm

f=-10

so,v1=-20.

case two

the consider second end

it's distance from pole of mirror is 10+20=30.

then from above formula.

v2=-15

the image size is =20-15=5cm

(note the v=-20 and -15 here negative sign is the direction of image and nature. it's negative shinde will not be considered at time of v1-v2)

hope so helpful

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