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A paperweight in the form of a hemispher...

A paperweight in the form of a hemisphere of radius 3.0 cm is used to hold down a printed page. An observer looks at the page vertically through the paperweight. At what height above the page will the printed letters near the centre appear to the observer ?

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The correct Answer is:
B, D

`r=3cm u=3/2`
`mu_1=9`
v=9`

`mu_2/v-mu_1/u=(mu_2-mu_1)/r`
`rarr 9/v-3/(2xx(-3))=(1-5)/(-3)`
`- 1/v+1/2=1/6`
`rarr 1/v=1/v-1/2=(-2)/6` ltbgt `rarr 1/v=(-1)/3`
`rarr v=-3`
`:. U=v80 no shift.
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