The length of the column in an Hg thermometer is 5 cm at 0 $\circ$ C and 30 cm at 100 $\circ$ C.For a 20 cm length of column,the corresponding temperature is
A)60.
B)70.
C)80.
D)85.
E)90.

Question

Quizplus · Accepted Answer

The thermometer has a linear scale. The length of the column increases from 5 cm to 30 cm as the temperature increases from 0°C to 100°C. This means each 1 cm increase in length corresponds to a 4°C increase in temperature (100°C - 0°C = 100°C, 30 cm - 5 cm = 25 cm, 100°C/25 cm = 4°C/cm). For a 20 cm length, the increase from the 5 cm at 0°C is 15 cm, which corresponds to 15 cm * 4°C/cm = 60°C. Therefore, the temperature is 60°C.

The Length of the Column in an Hg Thermometer Is ∘\circ∘

The Length of the Column in an Hg Thermometer Is $\circ$