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In a slide show programme, the image on ...

In a slide show programme, the image on the screen has an area 900times that of the slide. If the distance between the slide and the screen is x times the distance between the slide and the projector lens, then

A

`x=30`

B

`x=31`

C

`x=500`

D

`x=1//30`

Text Solution

Verified by Experts

The correct Answer is:
b.
`m=30`
`v+u=xu`
or `(v)/(u)+1=x` or `m+1=x`
or `x=31`
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Knowledge Check

  • In a movie hall, the distance between the projector and the screen is increased by 1% illumination on the screen is

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