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Class 6 Science — Temperature and its measurement

Say why touch cannot judge hotness, read a thermometer correctly, and convert a Celsius temperature to the Kelvin scale.

Name: ________________________

Before you start

Slide along this laboratory thermometer's scale. Its range runs from one end to the other, and each small step is ten degrees.

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A clinical thermometer covers nothing like this stretch, which is why it cannot be used on boiling water or on ice.

  1. 1.Why are mercury clinical thermometers being replaced by digital ones?

    • a) Mercury thermometers give readings that are too precise
    • b) Digital thermometers do not need to touch the body
    • c) Mercury cannot measure body temperature
    • d) Mercury is extremely toxic and hard to deal with if the thermometer breaks

  2. 2.Can a clinical thermometer be used to measure the temperature of boiling water?

    • a) No, because boiling water has no temperature
    • b) Yes, but the reading has to be doubled
    • c) No — boiling water lies outside its range
    • d) Yes, if it is held in for long enough

  3. 3.A temperature of 37.0 °C on the Celsius scale is the same temperature as which reading on the Fahrenheit scale?

    • a) 100 °F
    • b) 273.15 °F
    • c) 98.6 °F
    • d) 37.0 °F

  4. 4.Put the steps for measuring the temperature of warm water with a laboratory thermometer back into order.

    • Dip the thermometer so the bulb is immersed, clear of the bottom and sides
    • Hold it vertically, without tilting it
    • Read it with your eye level with the top of the column, while it is still immersed
    • Wait until the liquid column stops rising

  5. 5.What liquid does the chapter say a laboratory thermometer generally holds?

    • a) Air on its own
    • b) Alcohol coloured red, or mercury
    • c) Oil coloured green
    • d) Water coloured blue

  6. 6.Why must a laboratory thermometer be read while its bulb is still in the water?

    • a) The glass cracks if it is lifted out too quickly
    • b) The scale becomes unreadable out of water
    • c) The reading takes an hour to settle
    • d) The liquid column starts to fall the moment it is taken out

  7. 7.One hand comes out of warm water and the other out of ice-cold water. Both go into the same bowl of tap water, and they report different things. What does the chapter conclude?

    • a) Warm water makes whatever follows feel cold
    • b) The tap water changed temperature in between
    • c) Touch is not a reliable way to decide how hot something is
    • d) One of the hands is faulty

  8. 8.A thermometer that reads a person's temperature without touching them has a name in the chapter. Which is it?

    • a) A laboratory thermometer
    • b) A mercury thermometer
    • c) A clinical thermometer
    • d) A non-contact, or infrared, thermometer

Answer key — Class 6 Science — Temperature and its measurement

  1. 1. d) Mercury is extremely toxic and hard to deal with if the thermometer breaks
  2. 2. c) No — boiling water lies outside its range
  3. 3. c) 98.6 °F
  4. 4. 1. Dip the thermometer so the bulb is immersed, clear of the bottom and sides 2. Hold it vertically, without tilting it 3. Wait until the liquid column stops rising 4. Read it with your eye level with the top of the column, while it is still immersed
  5. 5. b) Alcohol coloured red, or mercury
  6. 6. d) The liquid column starts to fall the moment it is taken out
  7. 7. c) Touch is not a reliable way to decide how hot something is
  8. 8. d) A non-contact, or infrared, thermometer