Please help with this YDSE problem.

The figure shows a YDSE set-up. The source S of wavelength $\lambda = 4000 A^{\circ}$ oscillates along the y-axis according to the equation $y = \sin(\pi t)$ where $y$ is in millimetres and $t$ is in seconds. The distance between the two slits is $0.5 \text{ mm}$ . Answer the following questions:

Q. The instant at which maximum intensity occurs at $P$ for the first time is:

$\dfrac{1}{\pi} \arcsin \left( \dfrac{59}{160} \right)$
$\dfrac{1}{\pi} \arcsin \left( \dfrac{59}{80} \right)$
$\dfrac{1}{\pi} \arcsin \left( \dfrac{27}{160} \right)$
$\dfrac{1}{\pi} \arcsin \left( \dfrac{27}{80} \right)$

Q. The instant at which minimum intensity occurs at $P$ for the first time is:

$\dfrac{1}{\pi} \arcsin \left( \dfrac{59}{160} \right)$
$\dfrac{1}{\pi} \arcsin \left( \dfrac{59}{80} \right)$
$\dfrac{1}{\pi} \arcsin \left( \dfrac{27}{160} \right)$
$\dfrac{1}{\pi} \arcsin \left( \dfrac{27}{80} \right)$

#Mechanics

Easy Math Editor

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
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`\frac{2}{3}`	$\frac{2}{3}$
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Comments

@Steven Chase @Mark Hennings @Md Zuhair Please help.

Tapas Mazumdar - 3 years, 1 month ago

Question 1- (B)?

Sahil Silare - 3 years, 1 month ago

Question 2-(D)?

Sahil Silare - 3 years, 1 month ago

@Sahil Silare can u write the solution

A Former Brilliant Member - 3 years, 1 month ago

I'm bad with latex but what I did was adding up the path difference from source to slits and slits to screen and then it will be equal to n(lambda) for maximum.

Sahil Silare - 3 years, 1 month ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$