To find the length of the mercury thread, we need to know the coefficient of linear expansion of the substance used in the thermometer. The coefficient of linear expansion is a measure of how much a material expands or contracts per degree change in temperature.
Once we have the coefficient of linear expansion, we can use the formula:
ΔL = α * L * ΔT
Where:
- ΔL is the change in length of the substance
- α is the coefficient of linear expansion
- L is the original length of the substance
- ΔT is the change in temperature
Since we are given that the distance between the fixed points on the thermometer is 20 cm, we can assume this is the original length (L) of the mercury thread.
Assuming the coefficient of linear expansion for mercury is 0.000181 per °C, and the change in temperature (ΔT) is 100°C (from 0°C to 100°C), we can calculate the change in length (ΔL):
ΔL = 0.000181 * 20 cm * 100°C
= 0.362 cm
Therefore, the length of the mercury thread when the temperature is 100°C would be the original length (20 cm) plus the change in length (0.362 cm):
Length = 20 cm + 0.362 cm
= 20.362 cm
So, the length of the mercury thread at 100°C would be approximately 20.362 centimeters.
A thermometer has a distance of 20cm between the two fixed points , what is the length of the mercury thread when the temperature is 100°c
1 answer
1 answer