Advertisements
Advertisements
Question
You may have noticed that a few sharp jerks are given to a clinical thermometer before using it. Why is it done so?
Advertisements
Solution
A clinical thermometer has a kink that prevents immediate backflow of the mercury from the tube to the bulb, thus allowing us to read the temperature conveniently. This is the reason why we give a jerk to the thermometer before taking a new reading. The jerk positions the mercury below the kink into the bulb.
APPEARS IN
RELATED QUESTIONS
A thermometer is used to measure ______.
Describe a clinical thermometer. How does it differ from the thermometer used in laboratory?
Match the following
| i. | Clinical thermometer | A form of energy |
| ii. | Normal temperature of human body | 100°C |
| iii. | Heat | 37°C |
| iv. | Boiling point of water | 0°C |
| v. | Melting point of water | Kink |
State the similarities and differences between the laboratory thermometer and the clinical thermometer
Digital thermometers do not use ______.
Mercury is a poor conductor of heat.
We are advised to avoid keeping the clinical thermometer in the sun or near a flame. Why?
Explains the properties of mercury.
A laboratory thermometer A is kept 7 cm away on the side of the flame while a similar thermometer B is kept 7 cm above the flame of a candle as shown in the following figure.

Which of the thermometers, A or B, will show a greater rise in temperature? Give reason for your answer.
A solid metallic cube having a total surface area of 24 m2 is uniformly heated. If its temperature is increased by 10°C, calculate the increase in the volume of the cube.
(Given: α = 5.0 × 10-4°C-1)
