Question

In young 's double slit experiment the two coherent sources have different amplitudes. If the ratio of maximum intensity to minimum intensity is 16 : 1, then the ratio of amplitudes of the two source will be _______.

Options

• 4 : 1

• 5 : 3

• 1 : 4

• 1 : 16

Answer 1

In young 's double slit experiment the two coherent sources have different amplitudes. If the ratio of maximum intensity to minimum intensity is 16 : 1, then the ratio of amplitudes of the two source will be 5 : 3.

Explanation:

`"I"_"max"/"I"_"min" = 16/1`

`"I"_"max"/"I"_"min" = ("a"_1 + "a"_2)^2/("a"_1 - "a"_2)^2 = 16/1`

`"I"_"max"/"I"_"min" = 16/1`

`therefore ("a"_1 + "a"_2)/("a"_1 - "a"_2) = 4/1`

∴ a₁ + a₂ = 4a₁ - 4a₂

∴ 3a₁ = 5a₂ 

∴ `"a"_1/"a"_2 = 5/3`