Single Choice

In Young's double slit interference experiment the slit separation is made $$3$$ fold. The fringe width becomes

A$$1/3$$ times
Correct Answer
B$$1/9$$ times
C$$3$$ times
D$$9$$ times

Solution

The fringe width is given as:
$$\beta=\dfrac{D\lambda}{d}$$

$$\beta \propto \dfrac 1d $$

$$\Rightarrow $$ If $$d$$ becomes thric, then $$\beta$$ become becomes $$\dfrac 13$$


SIMILAR QUESTIONS

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