Question

Volume of mercury in the bulb of a thermo-
meter is 10-6m3. Area of cross section of
capillary tube is 2 x 10-7m2. If the temperature
is raised by 100°C, the length of mercury
column is (7.-=18 x 10-5/°C)
Hg

Answer 1

Given: Volume of mercury in the bulb of a thermometer is 10^-6 m^3.

To find: the length of mercury  column ?

Solution:

• Now we have given:

• Volume of mercury in the bulb of a thermometer is 10^-6 m^3, area of cross section of  capillary tube is 2 x 10^-7 m^2.

• Now change in volume is:

                     ΔV = VγΔT

• Putting the values in it, we get:

                     ΔV = 10^-6 x 18 x 10^-5 x  100

                     ΔV = 10^-9 x 18

• Now ΔV = A x ΔL

• Putting the values in it, we get:

                     10^-9 x 18 = 2 x 10^-7 x ΔL

                     ΔL = 10^-9 x 18 / 2 x 10^-7

                     ΔL = 9 X 10^-2 m

                     ΔL = 9 cm

Answer:

              So the length of mercury  column is 9 cm.