Page 111 - Physics - XII
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6. Remove the glass slab and draw a straight line through R, S which represent emergent ray and meets
face DC at Y. Draw a normal N N at Y and join XY. Measure the angle N YR, i.e., angle e which comes
4
3
4
to be equal to angle i.
7. Produce PQX forward to cut DC at Z. Draw TZ perpendicular to RSY. TZ measures the lateral
displacement ‘d ’.
8. Repeat the experiment by taking the glass slabs of diff erent thickness.
N 1
P
Q
Angle of incidence
i
A X Air B
N
3 Glass
r Glass slab
Refracted
ray
Angle of
refraction
r
N
2
Z
D Y d C
e
Angle of T R
emergence
Lateral
S displacement
d
N
4
Emergent ray
Fig. 4.1: Refraction of ray of light through a glass slab
Observations
Least count of protractor = _____ degree
Least count of metre scale = _____ mm = _____ cm
S. Thickness of glass slab, Angle of incidence, Angle of emergence, Lateral deviation,
No. t (cm) ∠i (degree) ∠e (degree) d (cm)
1. t 1
2. t 2
3. t 3
4. t 4
5. t 5
6. t 6
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