NEET 2025: Wave Optics PYQs with Answers

Q 1 :
Interference pattern can be observed due to superposition of the following waves:

A. $y = a \sin ω t$

B. $y = a \sin 2 ω t$

C. $y = a \sin (ω t - ϕ)$

D. $y = a \sin 3 ω t$

Choose the correct answer from the options given below: [2024]

B and C
B and D
A and C
A and B

(3)

For obtaining interference pattern, the two superimposing waves should be of same frequency. It is clear from the given options that waves in option A and C have same frequency, so they will superimpose and give interference pattern.

Q 2 :
The interference pattern is obtained with two coherent light sources of intensity ratio $n$ . In the interference pattern, the ratio $\frac{I_{max} - I_{min}}{I_{max} + I_{min}}$ will be [2016]

$\frac{\sqrt{n}}{n + 1}$
$\frac{2 \sqrt{n}}{n + 1}$
$\frac{\sqrt{n}}{{(n + 1)}^{2}}$
$\frac{2 \sqrt{n}}{{(n + 1)}^{2}}$

(2)

Here, $\frac{I_{1}}{I_{2}} = n$

$\frac{I_{max}}{I_{min}} = {(\frac{\sqrt{I_{1}} + \sqrt{I_{2}}}{\sqrt{I_{1}} - \sqrt{I_{2}}})}^{2} = {(\frac{\sqrt{I_{1} / I_{2}} + 1}{\sqrt{I_{1} / I_{2}} - 1})}^{2} = {(\frac{\sqrt{n} + 1}{\sqrt{n} - 1})}^{2}$

$\frac{I_{max} - I_{min}}{I_{max} + I_{min}} = \frac{\frac{I_{max}}{I_{min}} - 1}{\frac{I_{max}}{I_{min}} + 1}$

$= \frac{{(\frac{\sqrt{n} + 1}{\sqrt{n} - 1})}^{2} - 1}{{(\frac{\sqrt{n} + 1}{\sqrt{n} - 1})}^{2} + 1} = \frac{{(\sqrt{n} + 1)}^{2} - {(\sqrt{n} - 1)}^{2}}{{(\sqrt{n} + 1)}^{2} + {(\sqrt{n} - 1)}^{2}}$ $= \frac{4 \sqrt{n}}{2 (n + 1)} = \frac{2 \sqrt{n}}{n + 1}$

Topic Question Set

Q 1 :
Interference pattern can be observed due to superposition of the following waves:

A. $y = a \sin ω t$

B. $y = a \sin 2 ω t$

C. $y = a \sin (ω t - ϕ)$

D. $y = a \sin 3 ω t$

Choose the correct answer from the options given below: [2024]

Q 2 :
The interference pattern is obtained with two coherent light sources of intensity ratio $n$ . In the interference pattern, the ratio $\frac{I_{max} - I_{min}}{I_{max} + I_{min}}$ will be [2016]

Want Us to Email you About Special Offers & Updates?

Topic Question Set

Q 1 : Interference pattern can be observed due to superposition of the following waves: A. y=asinωt B. y=asin2ωt C. y=asin(ωt-ϕ) D. y=asin3ωt Choose the correct answer from the options given below: [2024]

Q 2 : The interference pattern is obtained with two coherent light sources of intensity ratio n. In the interference pattern, the ratio Imax-IminImax+Imin will be [2016]

Want Us to Email you About Special Offers & Updates?

Q 1 :
Interference pattern can be observed due to superposition of the following waves:

A. $y = a \sin ω t$

B. $y = a \sin 2 ω t$

C. $y = a \sin (ω t - ϕ)$

D. $y = a \sin 3 ω t$

Choose the correct answer from the options given below: [2024]

Q 2 :
The interference pattern is obtained with two coherent light sources of intensity ratio $n$ . In the interference pattern, the ratio $\frac{I_{max} - I_{min}}{I_{max} + I_{min}}$ will be [2016]