LAB #10: Lenses and Spherical Mirrors
Theory:
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What are lenses?
What is difference between converging and diverging lenses?
Lens equation. Sign convention.
What is spherical mirror?
Spherical mirror equation and sign convention.
Experiment:
LENSES
fmeas.
1. For both lenses A and C find fmeas by focusing the room light on the table and
measuring the distance from the table to the lens. Use estimated error.
fcalc
2. Set up optical bench as in Figure 10.4. Move lens until image is in focus. Record
object, lens and image position. Calculate O and I and f using eq.10.1. Repeat
procedure for other lens.
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Compare fmeas with fcalc
MIRRORS
Rcalc
1. Set up optical bench as in Figure 10.5 (object is the bulb). Move screen until
image is in focus. Record object, mirror and image position. Calculate O and I
and Rcalc using eq. 10.2.
Rknown
2. Calculate Rknown
T-glass plate thickness
t-mirror thickness
X-thickness of “mirror on plate”
H=X-T-t
• Mesure T, t and X using caliper
• Calculate h±δh
• Calculate Rknown±δRknown
• Compare Rcalc with Rknown
Note: δ (
A
δX
) = A 2 where A is constant
X
X