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प्रश्न
At what distance from a concave mirror of focal length 10 cm should an object be placed so that:
its virtual image is formed 20 cm from the mirror?
उत्तर
Given
Given,f=−10 cm v=+20 cm Since the image is virtual and forms behind the mirror, the equation will be
`1/f=1/v+1/u`
`1/-10=1/20+1/u`
`-1/10-1/20=1/u`
`1/u=(-20-10)/200`
`1/u=(-30)/200`
`1/u=(-3)/20`
`u=-20/3`
संबंधित प्रश्न
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