MHTCET 14 May 2023 Shift 2 Solved Paper

To calculate the frequency of light when the wavelength is given, we can use the relationship between speed, frequency, and wavelength. This relationship is given by the equation:
c=λ⋅ν
where:
c is the speed of light in a vacuum (c≈3×108m∕ s),
λ is the wavelength in meters,
ν(nu)‌ is the frequency in hertz ‌(Hz)‌. ‌
To find the frequency, we can rearrange the equation to solve for ν :
ν=‌

c

λ

Given that the wavelength is 750‌nm (nanometers), we have to convert the wavelength into meters for our calculations because the speed of light is in meters per second. There are 1×109 nanometers in one meter, so:
750‌nm=750×10−9m
Now, let's insert the values for c and λ into our equation:
ν=‌

3×108m∕ s

750×10−9m

Calculating the frequency ν :
‌ν=‌

3×108

750×10−9

=‌

3×108

0.75×10−6

=‌

3

0.75

×108+6
‌ν=4×1014‌Hz
Therefore, the frequency of light with a wavelength of 750‌nm is 4×1014‌Hz, which corresponds to Option B.