Aammar Paracha
Section MX
Feb 6th 2015 OPTICS
Abstract:
This experiment revolves around using light rays and lenses. The experiment also discusses different properties of light rays. This experiment uses different lenses and measurements to produce images and observes different techniques to obtain the image position.
Question and Answers:
1. Use your data to verify the Law of Reflection and then use Snell's Law to calculate the refractive index for water (nw) .
The data showed that the value of theta in both the tanks were approximately same thus proving the law of reflection.
Value of Refractive index of water for tank 1= 1.68
Value of Refracive Index of water for tank 2=1.35
2. What is the focal length of the lens used in section 1.3 “Focal Length” of your manual? Can you deduce from the image seen, if the lens used was converging or diverging?
The focal length of the lens used is calculated to be 31 mm. The lens used in the experiment was a converging lens as the image was
3. Calculate the focal length of the given converging lens based on the measurements of s and s ' and thin lens equation. Tabulate your results (for all the three trials). Compare ratios of the image and object distances and heights for the three object distances to show−(s' / s) = (h' / h) is true. Draw a ray diagram and show the different lengths for one trial.
The equation can be proven by using the first trial in the experiment.
-(310)/(140) = (950)/(430)
2.21 = 2.21
Real Images
object s (mm) image s' (mm) object h (mm) image h' focal length f (mm)
140
310
430
950
96.4
175
215
430
500
96.4
140
325
430
900
97.9
220
175
430
310
97.4
4. Use the parallax method described in the lab manual to determine the focal length of the lens.Compare this length to the previously calculated values.
The value of the focal length using the parallax method is 96.4 mm. The average value of the focal