﻿ A particle moves towards a concave mirror of focal length 30 cm along its axis and with a constant speed of 4 cm/ sec. What is the speed of its image when the particle is at 90 cm from the mirror? : Kaysons Education

# A Particle Moves Towards A Concave Mirror Of Focal Length 30 Cm Along Its Axis And With A Constant Speed Of 4 Cm/ Sec. What Is The Speed Of Its Image When The Particle Is At 90 Cm From The Mirror?

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## Question

### Solution

Correct option is

1 cm/sec

We know that if

Then,

Use,

⇒                 v = – 45 cm

Substitute the values

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