1 Lab Assignment #5 Write-Up

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General Info:
Name:
Date:

Purpose: Of Exp #5: In this experiment we will learn about the spectroscope and how it works. To learn the concept of quantitative measurements, to construct a spectroscope and, to use it for taking quantitative measurements.

Experimental Questions:
Please complete this section of your write-up as you work on the experimental portion of this lab.

1. Hold the grating several inches from your face, at an angle. Look at the grating that you will be using. Describe what you see at the grating surface. I see different color of the rainbow and when I change the angle that am holding the diffraction grating

Hold the grating up to your eye and look through it.
2. The violet Hg emission spectral line at 436 nm was used as the reference in calibrating your spectroscope. Look in your textbook or other information source. What is the wavelength range for violet light? It’s between 380 and 450.

If you are viewing a spectrum from another light source, and it has a violet line, should you expect that line to be centered on the reference mark on your light rod? I think my answer for this question will be kind of yes, because even if we are using different light source our spectrum should give us the same reading or range for our lights.

If it is not centered on the reference mark, what can you conclude about the wavelength of this new violet line? The reason can be that this source of light contain different amount(lines) of colors than the original source I used and it might have more violet color than the original source I used.

Should you move your light rod? Why or why not? No, because we just calibrated our spectrum and it should give us good reading for any light source.

3. Now that you have calibrated your light rod, list the wavelengths for each colored line that you see in the spectrum of your fluorescent light. (See “Help Me!!” section at the end of this lab for help). You can use the picture you drew in question 1 of the calibration procedure to get spaces from reference line for each color, and use your final