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Specific heat of water is 4.2 J//g.^(@)C...

Specific heat of water is `4.2 J//g.^(@)C`. If light of frequency `3 xx 10^(29)Hz` is used to heat 400 g of water from `20^(@)C` to `40^(@)C`, the number of moles of photons needed will be

A

`1.69xx 10^(29)`

B

`1.69 xx 10^(28)`

C

`2.80 xx 10^(4)`

D

`2.80 xx 10^(5)`

Text Solution

Verified by Experts

The correct Answer is:
D
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