When an object is placed at a distance of 15cm from a concave mirror,its image is formed at 10cm in front of the mirror.calculate the focal length of the mirror.

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Solution

Dear Student

According to mirror formula-

1/f = 1/v+1/u
where f=focal length, v=image distance, u=object distance

v = -10 cm (as object is on left side)

u = -15 cm (as image formed is also on left side)

Therefore, 1/f = -1/10 + (-1/15)

1/f = -1/6

f = -6 cm

Regards

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When an object is placed at a distance of 15cm from a concave mirror,its image is formed at 10cm in front of the mirror.calculate the focal length of the mirror.

Dear Student According to mirror formula- 1/f = 1/v+1/u where f=focal length, v=image distance, u=object distance v = -10 cm (as object is on left side) u = -15 cm (as image formed is also on left side) Therefore, 1/f = -1/10 + (-1/15) 1/f = -1/6 f = -6 cm Regards

Dear Student

According to mirror formula-

1/f = 1/v+1/u
where f=focal length, v=image distance, u=object distance

v = -10 cm (as object is on left side)

u = -15 cm (as image formed is also on left side)

Therefore, 1/f = -1/10 + (-1/15)

1/f = -1/6

f = -6 cm

Regards