Chapter 7 Solutions — Temperature and its Measurement

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1. 1.
   The normal temperature of a healthy human being is close to ___.

   • (i) 98.6 °C
   • (ii) 37.0 °C
   • (iii) 32.0 °C
   • (iv) 27.0 °C
2. 2.
   37 °C is the same temperature as ___.

   • (i) 97.4 °F
   • (ii) 97.6 °F
   • (iii) 98.4 °F
   • (iv) 98.6 °F
3. 3.
   Fill in the blanks:

   • (i) The hotness or coldness of a system is determined by its ___.
   • (ii) The temperature of ice-cold water cannot be measured by a ___ thermometer.
   • (iii) The unit of temperature is degree ___.
4. 4.
   The range of a laboratory thermometer is usually ___.

   • (i) 10 °C to 100 °C
   • (ii) –10 °C to 110 °C
   • (iii) 32 °C to 45 °C
   • (iv) 35 °C to 42 °C
5. 5.
   Four students used a laboratory thermometer to measure the temperature of water as shown in Fig. 7.6. Who do you think followed the correct way for measuring temperature?

   • (i) Student 1
   • (ii) Student 2
   • (iii) Student 3
   • (iv) Student 4
6. 6.
   Colour to show the red column on the drawings of thermometers (Fig. 7.7) as per the temperatures written below: 14 °C, 17 °C, 7.5 °C.
7. 7.
   Observe the part of thermometer shown in Fig. 7.8 and answer the following questions:

   • (i) What type of thermometer is it?
   • (ii) What is the reading of the thermometer?
   • (iii) What is the smallest value that this thermometer can measure?
8. 8.
   A laboratory thermometer is not used to measure our body temperature. Give a reason.
9. 9.
   Vaishnavi has not gone to school as she is ill. Her mother has kept a record of her body temperature for three days as shown in Table 7.4. Table 7.4: Body temperature record of Vaishnavi DAY | 7am | 10am | 1pm | 4pm | 7pm | 10pm One | 38.0 °C | 37.8 °C | 38.0 °C | 38.0 °C | 40.0 °C | 39.0 °C Two | 38.6 °C | 38.8 °C | 39.0 °C | 39.0 °C | 39.0 °C | 38.0 °C Three | 37.6 °C | 37.4 °C | 37.2 °C |…
10. 10.
    If you have to measure the temperature 22.5 °C, which of the following three thermometers will you use (Fig. 7.9)? Explain.
11. 11.
    The temperature shown by the thermometer in Fig. 7.10 is

    • (i) 28.0 °C
    • (ii) 27.5 °C
    • (iii) 26.5 °C
    • (iv) 25.3 °C
12. 12.
    A laboratory thermometer has 50 divisions between 0 °C and 100 °C. What does each division of this thermometer measure?
13. 13.
    Draw the scale of a thermometer in which the smallest division reads 0.5 °C. You may draw only the portion between 10 °C and 20 °C.
14. 14.
    Komal tells you that she has a fever of 101 degrees. Does she mean it on the Celsius scale or Fahrenheit scale?