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How fast a person should drive his car s...

How fast a person should drive his car so that the red signal fo light apperas green ?
( Wavelength for red colour = 6200 Å and wavelength for green colour = 5400 Å)

A

`1.5 xx 10^8 m//s`

B

`7 xx 10^7 m//s`

C

`3.9 xx 10^7 m//s`

D

`2 xx 10^8 m//s`

Text Solution

Verified by Experts

The correct Answer is:
C
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