1. Open this simulation: htps:/phet.colorado.edu/sims/html/wave-interferencelatest/wave-interference en.html Click on "slits". You have three choices, water waves, sound and light. o Chose the light tab. Make sure both "screen" and "intensity" are checked. Choose "Two slits" with the smallest possible slit width of 200 nm. Set the amplitude to a maximum and keep the frequency right in the middle (green light). Leave the barrier in the default middle position. (a) What is the distance from the central bright fringe to the closest dark fringe? (b) What is the distance from the central bright fringe to the next bright fringe? Note that you can grab and drag the measuring tape from the top right in the simulation in order to make distance measurements. 2. Use the above information to detemine the wavelength of your green light source 3. Now increase the distance between the screen and the barrier by 1500 nm (You can click on the two-sided arrow below the barrier and then drag it to the left and right). How does the distance between the bright spots change? Deternmine the wavelength again using the new setup . 4. Suppose that the distance between the slits were inereased. Would the pattem "spread out or become"more compact? After you have made your predietion, check by increasing the separation. Change the separation between the slots to 2000 nm, measure the distances and determine the wavelength. 5. Predict what Wil happen to the fringes if you increase the frequency to the biuc iag it to the red range. Now perform a numerical experiment to find the wavelengths as in part8 Record all measured length and extract the frequencies of your chosen blue and red lights from the data 6. Predict what happens to (a) the locations and (b) the brightness of the fringes if we decrease the amplitude to half of its maximum value. Now test your prediction using the simulation. 7. Suppose the distance between the slits were held constant. To make the pattern become more compact, should the wavelength of the light be increased or decreased? Explain