Question

The legs of a spherometer are 5 cm apart. There are 10 division cm^-1 on linear scale and circular scale has 100 divisions. The height h of a convex mirror measured is 2 MSD + 37 circular scales divisions. Find radius of curvature of convex mirror.

• A. 20.003 cm
• B. 18.408 cm
• C. 17.399 cm
• D. 17.983 cm

Answer 1

Answer: (A)

20.003 cm

Answer 2

Least count = $\frac{1/10}{100} = 10^{- 3}$ cm

h = 2 × (0.1) + 37(10^-3) = 0.237 cm

R = $\frac{l^{2}}{6h} + \frac{h}{2} = \frac{25}{1.362} + 0.118 = 18.408cm$