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Q

for plane mirror: if the object moves with a velocity 'u' then the image moves with velocity 2u.how?

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0 , under Reflection of Light by Spherical ... by Harshall Pandit , added 1 year, 10 months ago comment

2 answers

A
If the mirror approaches u with speed v. then image will appear to approach u with speed 2v.. Because wrt the mirror the image moves with speed v and wrt ground it will move with v(wrt mirror) + v(of mirror) = 2v
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0 for Q. for plane mirror: if the object moves with a... answer added by Muskaan Talwar 1 year, 10 months ago comment

A

Detailed explanation is here: Distance of Image formed in the mirror is same as the distance of the object form the surface of the mirror.

Thus is distance of object = u

Then distance of image = -u (as the image is formed at other side of the mirror)

Thus distance between image and object = 2u ...(1)

Now if mirroe is approaching you/object with speed v, then distance travelled by mirror in unit time = v units

Thus distance between mirror and object in unit time = u - v

Thus disatnce between object and its image = 2(u-v)....(2)

From equations (1) and (2) distance between image and object is reduced by 2v units in unit time(1 second)

Thus speed of image w.r.t object = 2v

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0 for Q. for plane mirror: if the object moves with a... answer added by Muskaan Talwar 1 year, 10 months ago comment