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A large temple has a depression in one w...

A large temple has a depression in one wall.On ht floor plan is appers as a indentation having spherical shape of radius `2.50m`A worshipper stands one the center line of the depression,`2.00`m out from its deepest point,and whispers a prayers.Where is the sound concentrated after reflection fromt he back wall of the depression?

Text Solution

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The correct Answer is:
`((10)/(3)m)`
wall will act as concave mirror
`(1)/(v)+(1)/(u)=(1)/(f)implies (1)/(v)+(1)/(u)=(2)/(R )rArr(1)/(v)+(1)/(-2)=(2)/(-2.5)`
`(1)/(v)=(2)/(-2.5)+(1)/(2)rArr(1)/(v)=(-8+5)/(10)`
`(1)/(v)=(-3)/(10)`
`v=(-10)/(3)m`
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