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In an experiment on photo electric effec...

In an experiment on photo electric effect, the slope of cut - off voltage versus frequency, incident light is found to be `4.12 xx 10^(-15)` Vs. Calculate the of Planck's constant.

A

`6.6xx10^(-34)Js`

B

`3.3xx10^(-34)Js`

C

`2.2xx10^(-34)Js`

D

None of these.

Text Solution

Verified by Experts

The correct Answer is:
A
The slope of the graph in this case is
`4.12xx10^(-15)=(hc)/(e)`
`:. h=4.12xx10^(-15)xxe`
`=4.12xx10^(-15)xx1.6xx10^(-19)`
`=6.529xx10^(-34)Js`.
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