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If the wavelength of light is 4000 A, th...

If the wavelength of light is 4000 A, then the number of waves in 1 mm length will be ......

A

25

B

250

C

2500

D

25000

Text Solution

Verified by Experts

The correct Answer is:
C
Number of waves `n=(10^(-3))/(lambda)`
`=(10^(3))/(4xx10^(-7))=(10^(4))/(4)`
`=0.25xx10^(4)=2500`
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