- 65

- 4

- Homework Statement
- In a double slit experiment let d=5.00 D=30.0λ. Estimate the ratio of the intensity of the third order maximum with that of the zero-order maximum.

- Homework Equations
- interference diffraction

**Homework Statement:**In a double slit experiment let d=5.00 D=30.0λ. Estimate the ratio of the intensity of the third order maximum with that of the zero-order maximum.

**Homework Equations:**interference diffraction

i guess the goal is this equation

##I_{(\theta)}=I_0 \times(cos^2\beta)\times \left ( \frac {sin\alpha} \alpha \right)^2##

then i do

## D\sin \theta = 3\lambda##

##\sin\theta= \frac {3\lambda} D, \space \theta=5.74^0##

##\beta= \frac {\pi d} \lambda \sin \theta##

##\alpha = \frac {\pi D} \lambda \sin \theta \space##

substituting the data

##\alpha=\frac {\pi 30.0\lambda} \lambda \frac {3\lambda} {30.0\lambda}\space##

next

##\beta= \frac {\pi 5.00} \lambda \frac {3\lambda} {30.0\lambda}## i don't know how to solve this one, and solve the rest of the problem, how do i get rid of ##\space\lambda\space## at denominator?

any help please?