Describe with aid of diagrams 5 types of thermometers

Answers

1. Liquid-in-glass thermometer – this applies to the expansion of a liquid in a thin-walled glass-tube. The liquid moves up the tube when the bulb is heated. The liquid must be a good conductor, visible and be able to contract and expand quickly and uniformly over a wide range of temperatures. It should also not stick on the sides of the tube. Liquids commonly used are mercury and coloured alcohol. The scale is obtained by choosing two temperature points called fixed points. In Celsius lower point is taken to be 0^oC (when placed in ice) and the upper point as 100^oC (boiling steam). The two points are therefore divided into 100 equal parts (calibration). The melting and boiling points of both mercury and alcohol are (-39 ^oC – 357 ^oC) and (-112 ^oC - 78 ^oC) respectively.
2. Clinical thermometer– this is a special type of mercury-in-glass thermometer used to measure body temperature. Since body temperature is normally 37 ^oC the scale is only a few degrees below and above 37^oC. It has a constriction which prevents mercury from going back after expansion for convenient reading of temperature. This thermometer has a narrow bore for greater sensitivity and accuracy.

3. Six’s maximum and minimum thermometer– it is used to measure temperature of surroundings of an area or a place. It can record both maximum and minimum temperatures attained. Consists of a large bulb (A) containing oil of creosote connected to U-shaped stem which connects to a second bulb (B) containing the same liquid. The base (C) contains a thin thread of mercury. The range of this thermometer is between -20 ^oC and 50 ^oC. After each reading the indices are pulled down to the level of mercury by use of a magnet.

4. Bimetallic thermometer– it is made up of a bimetallic strip with one end fixed and the other connected to a pointer. Metals used are usually brass and invar. As temperatures increase the strip unwinds and moves the pointer over a calibrated scale. It is used to measure high temperatures.

5. Thermocouple thermometer– thermocouple is a junction made of copper and iron looped at both ends. In practice a sensitive millivoltmeter is used instead of a galvanometer. A cold junction is maintained in melting ice (0^oC) while the other junction is heated steadily. This thermometer does not apply the principle of expansion.

raphael answered the question on October 11, 2018 at 04:41

Next: Describe an experiment to show expansion of gases
Previous: Describe the unusual expansion of water, with aid of diagrams

View More Physics Questions and Answers | Return to Questions Index

Exams With Marking Schemes

Related Questions

Describe an experiment to show expansion of gases(Solved)
Describe an experiment to show expansion of gases

Date posted: October 11, 2018. Answers (1)
Describe the applications of the expansion of solids(Solved)
Describe the applications of the expansion of solids.

Date posted: October 9, 2018. Answers (1)
Describe the experiment to investigate actual expansion of solids, using a bimetallic strip(Solved)
Describe the experiment to investigate actual expansion of solids, using a bimetallic strip.

Date posted: October 9, 2018. Answers (1)
Describe the bar-breaker experiment(Solved)
Describe the bar-breaker experiment.

Date posted: October 9, 2018. Answers (1)

Describe the ball and ring experiment(Solved)
Describe the ball and ring experiment.

Date posted: October 9, 2018. Answers (1)
Outline ways in which matter can be changed(Solved)
Outline ways in which matter can be changed.

Date posted: October 9, 2018. Answers (1)
Application of pressure in gases and liquids(Solved)
Application of pressure in gases and liquids.

Date posted: October 9, 2018. Answers (1)
With the aid of diagrams, describe four devices used in measuring pressure(Solved)
With the aid of diagrams, describe four devices used in measuring pressure

Date posted: October 9, 2018. Answers (1)

A man blows into one end of a U-tube containing water until the levels differ by 40.0 cm. if the atmospheric pressure is 1.01 ×...(Solved)
A man blows into one end of a U-tube containing water until the levels differ by 40.0 cm. if the atmospheric pressure is 1.01 × 105 N/m² and the density of water is 1000 kg/m³, calculate his lung pressure.

Date posted: October 9, 2018. Answers (1)
The height of the mercury column in a barometer is found to be 67.0 cm at a certain place. What would be the height of...(Solved)
The height of the mercury column in a barometer is found to be 67.0 cm at a certain place. What would be the height of a water barometer at the same place? (Densities of mercury and water are 1.36 × 104 kg/m³ and 1.0 × 103 kg/m³ respectively.)

Date posted: October 9, 2018. Answers (1)
A diver is 10 m below the surface of water in a dam. If the density of water is 1,000 kgm^-3, determine the pressure due...(Solved)
A diver is 10 m below the surface of water in a dam. If the density of water is 1,000 kgm^-3, determine the pressure due to the water on the diver. (Take g = 10 Nkg )

Date posted: October 9, 2018. Answers (1)
A rectangular brick of weight 10 N, measures 50 cm × 30 cm × 10 cm. calculate the values of the maximum and minimum pressures...(Solved)
A rectangular brick of weight 10 N, measures 50 cm × 30 cm × 10 cm. calculate the values of the maximum and minimum pressures which the block exert when resting on a horizontal table.

Date posted: October 9, 2018. Answers (1)
The length of a spring is 16.0 cm. its length becomes 20.0 cm when supporting a weight of 5.0 N. calculate the length of the...(Solved)
The length of a spring is 16.0 cm. its length becomes 20.0 cm when supporting a weight of 5.0 N. calculate the length of the spring when supporting a weight of: (a) 2.5 N (b) 6.0 N (c) 200 N

Date posted: October 9, 2018. Answers (1)
Outline the types of forces(Solved)
Outline the types of forces

Date posted: October 9, 2018. Answers (1)
State three properties of gamma rays which differ from that of alpha and beta particles(Solved)
State three properties of gamma rays which differ from that of alpha and beta particles.

Date posted: September 20, 2018. Answers (1)
The speed of sound in air is 340 m/s.A loudspeaker placed between two walls X and Y, but nearer to wall x than wall y,...(Solved)
The speed of sound in air is 340 m/s.A loudspeaker placed between two walls X and Y, but nearer to wall x than wall y, is sending out constant sound pulses.How far is the speaker from wall Y if it is 200 m from wall X and the time between the two echoes received is 0.176 s.

Date posted: September 17, 2018. Answers (1)
The ship sends out an ultrasound whose echo is received after 10s. If the wavelength of the ultrasound in water is 0.05 m and the...(Solved)
The ship sends out an ultrasound whose echo is received after 10s. If the wavelength of the ultrasound in water is 0.05m and the frequency of the transmitter is 50kHz, calculate the depth of the ocean

Date posted: September 17, 2018. Answers (1)
A cog wheel rotating uniformly produces sound of wavelength 1.65 m. If it makes 10 revolutions/second, find the number of teeth on the wheel, given...(Solved)
A cog wheel rotating uniformly produces sound of wavelength 1.65 m. If it makes 10 revolutions/second, find the number of teeth on the wheel, given that the velocity of sound in air is 330 m/s.

Date posted: September 17, 2018. Answers (1)
Two girls stand 200 m from a wall. One bangs two pieces of wood together while the second starts a stop watch and stops it...(Solved)
Two girls stand 200 m from a wall. One bangs two pieces of wood together while the second starts a stop watch and stops it when he hears the echo. If the time shown on the stop watch is 1.2 s, calculate the speed of sound.

Date posted: September 17, 2018. Answers (1)
It is noted that 250 cm^3 of fluid flows out of a tube, whose inner diameter is 7 mm,in a time of 41 s. What...(Solved)
It is noted that 250 cm^3 of fluid flows out of a tube, whose inner diameter is 7 mm,in a time of 41 s. What is the average velocity of the fluid in the tube?

Date posted: September 17, 2018. Answers (1)

Quick Links