Answer Happy

1. A red low-power laser with λ = 634nm was beamed at a double-slit grating. An interference pattern appeared on a screen 2.50 m from the grating. The distance from central spot to the next bright spot was 22.5cm. What is the spacing between the slits in the grating? 2. The red laser (in Q1) is replaced by a blue laser with a shorter wavelength. All else is the same. Show mathematically whether the interference pattern it produces will place the bright spots closer or further apart. 3. Given that the blue laser in Q2 has a wavelength of 445 nm, calculate the "spot-spacing" for the same slit grating and screen distance as in Q1. 4. A green laser beam produces spots which are 0.334m apart (central to m=1) when a grating is used with slits 3,000 nm apart and a screen 1.90m away. What is the wavelength of the laser light?