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
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.
To find the length of the mercury thread in a thermometer when the temperature is 100°C, we need to know the coefficient of linear expansion of mercury. The coefficient of linear expansion for mercury is approximately 0.000181 per degree Celsius.
Given that the distance between the two fixed points on the thermometer is 20cm, we can calculate the length of the mercury thread at 100°C using the following formula:
Length at 100°C = Initial Length + (Initial Length × Coefficient of Linear Expansion × Change in Temperature)
Change in Temperature = Final Temperature - Initial Temperature
Let's assume the initial temperature of the thermometer is 0°C.
Change in Temperature = 100°C - 0°C = 100°C
Using the given formula, the length of the mercury thread at 100°C can be calculated as:
Length at 100°C = 20cm + (20cm × 0.000181 per °C × 100°C)
Length at 100°C = 20cm + (20cm × 0.0181)
Length at 100°C = 20cm + 0.362cm
Length at 100°C ≈ 20.362cm
Therefore, the length of the mercury thread at 100°C is approximately 20.362cm.