A mercury thermometer has a glass bulb of interior volume 0.100 cm3 at 10°c. the glass capillary 10) tube above the bulb has an inner cross-sectional area of 0.012 mm2. the coefficient of volume expansion of mercury is 1.8 * 10-4 k-1. if the expansion of the glass is negligible, how much will the mercury rise in the capillary tube when the temperature rises from 5°c to 35°c if the bulb was full at 5°c?

Initial volume of mercury is

V = 0.1 cm³

The temperature rise is 35 - 5 = 30 ⁰C = 30 ⁰K.

Because the coefficient of volume expansion is 1.8x10⁻⁴ 1/K, the change in volume of the mercury is

ΔV = (1.8x10⁻⁴ 1/K) * (30 ⁰K) (0.1 cm³) = 5.4x10⁻⁴ cm³

The cross sectional area of the tube is

A = 0.012 mm² = (0.012x10⁻² cm²).

Therefore the rise of mercury in the tube is

h = ΔV/A

= (5.4x10⁻⁴ cm³) / (0.012x10⁻² cm²)

= 4.5 cm

Answer: 4.5 cm