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Question : 9
Total: 35
A beam of light travels from air into a medium. Its speed and wavelength in the medium are 1.5 × 10 8 ms − 1 230 nm
Solution: 👈: Video Solution
In the medium
c = n λ
or,1.5 × 10 8 = n × 230 × 10 − 9
or,n =
∴ n =
× 10 17 Hz
In air,
Frequency remains unchanged. So,
n =
× 10 17 Hz
v ′ = n λ ′
or, 3 × 10 8 =
× 10 17 × λ ′
∴ λ ′ = 3 ×
× 10 − 9
= 460 nm
or,
or,
In air,
Frequency remains unchanged. So,
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