The wavelength of the short radio waves, microwaves, ultraviolet waves are `lambda_(1),lambda_(2)` and `lambda_(3)`, respectively, Arrange them in dec

Monjur Alahi

The wavelength of the short radio waves, microwaves, ultraviolet waves are `lambda_(1),lambda_(2)` and `lambda_(3)`, respectively, Arrange them in decreasing order.
A. `lambda_(1),lambda_(2),lambda_(3)`
B. `lambda_(1),lambda_(3),lambda_(2)`
C. `lambda_(3),lambda_(2),lambda_(1)`
D. `lambda_(2),lambda_(1),lambda_(3)`


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Salim Ahmed Kawsar

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Correct Answer - A
we know that ,
(a) Short radio waves i.e., wavelength range
`= 1 xx 10^(-1) m` to `1 xx 10^(4) m`
(ii) Microwaves wavelength range
`= 1 xx 10^(-3) m` to `3 xx 10^(-1) m`
(iii). Ultraviolet waves wavelength range
`= 1 xx 10^(8) m` to `4 xx 10^(-8) m`
So, decreasing order is `lambda_(1), lambda_(2), lambda_(3)`.

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