Page 14 - Physics - XI

Observations

1. Vernier constant: Value of one main scale divisions (1 M.S.D.) = 1 mm
10 vernier scale divisions (V.S.D.) = 9 main scale divisions (M.S.D.)

i.e. 10 V.S.D. = 9 M.S.D. or 1 V.S.D. = 9 M.S.D.
10
Vernier constant (V.C.) = 1 M.S.D. – 1 V.S.D. = 1 M.S.D. – 9 M.S.D.
10
9 1 1
V.C. = 1 × 1 M.S.D. = × 1 M.S.D. = × 1 mm = 0.1 mm

10 10 10
V.C. = 0.01 cm

2. Zero error = (i) _________ cm (ii) _________ cm (iii) ___________ cm
Mean zero error = (e) = _________ cm

Mean zero correction = –e = ________ cm

Table for calculation of diameter of a cylindrical body or a spherical body

Observation Main scale No. of Vernier Vernier scale Observed Mean Mean
for x division reading diameter observed corrected
coinciding y = n × (V.C.) = x + y diameter D o diameter
(cm) (n) (cm) (cm) (cm) D = D + (–e)
o
i
(cm)
1.
Diameter I D =
2. 1

1.
Diameter II D =
2. 2
1.
Diameter III D =
2. 3

Table for calculation of internal diameter (d) of a calorimeter

S. No. Main scale No. of Vernier Vernier scale Observed internal Corrected
reading division reading diameter internal diameter
x coinciding y = n × (V.C.) d = x + y d = d + (–e)
o
i
o
(cm) (n) (cm) (cm) (cm)
1.
2.

3.

4.

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