Here are some questions to complete after you have determined the wavelength with a diffraction grating. (A laser was used)
equation used: n x lambda=d x sintheta
Question:
What effect will the following have on the pattern produced? Explain your reasoning:
1.increasing distance to screen, D
2.changing from red light to green light
3.rotating the diffraction grating through ninety degrees
4.using a point source of white light
2nd Attempt:(sorry the resource didnt help with this specifically so i just thought more)
1.Increasing the distance to the screen would mean would mean a bigger x1 which would mean a bigger angle and a bigger slit spacing. It would also mean a smaller wavelength.
2.Red light has a bigger wavelength than green light. Red light had 700nm while green light has around 500nm. As i know this fact i know that at the end of the experiment the wavelength i would find would be smaller than before if i used green light.
3.Rotating the diffraction grating would mean the wavelength also rotate and are no longer horizontal so wouldnt go through the slit.
4.White light is all sorts of wavelengths so it would cause the slit spacing and wavelength to increase.
I have gone through the text book, my work, websites, nothing gives information specific to these questions or anything that applies to them so im hoping someone can help ,me .I like this website for the teacher help. Maybe tell me if this is right and what else to say and if by pattern i just say increase/decrease.
2 answers
2. I think it is asking what happens to angles on Red vs Green. see what the angle (or the tan/sin of the angle does as wavelenth cnages)
3. with a point source, the pattern would be vertical, but without a point source, like a laser, you are right.
4. wavelength do not depend on the slit, or spacing, or distance. It is from the light. With many colors, you get overlapping patterns of individual patterns.
7 answers