Q1: State similarities and differences between the laboratory and clinicalthermometer.
Ans: Similarities:
1. Both consist of a long, narrow, uniform glass tube.
2. Both have a bulb containing mercury at the end of the tube.
3. Both are marked with Celsius scale on the glass tube.
Differences:
1. A clinical thermometer reads temperature from 350C to 420C, while a laboratory thermometer ranges between –100C to 1100C.
2. Clinical thermometer has a kink near the bulb while there is no kink in laboratory thermometer.
Q2: Give two examples each of conductors and insulators of heat.
Ans: Conductors of heat: copper, iron.
Insulators: wood, paper, plastic.
Conductors and Insulators
Q3:Fill in the blanks:
Ans: (a) temperature, (b) Celsius, (c) conduction, (d) clinical, (e) radiation, (f) dark
Q4: Match the items in column I with those in column II:
Column I | Column II |
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Ans: 1-d, 2-c, 3-b, 4-a.
Q5: Discuss why wearing more layers of clothing during winter keeps us warmer than wearing just one thick piece of clothing.
Ans: Wearing more layers of clothing during winter keeps us warmer than wearing just one thick piece of clothing because of the air trapped between two layers of clothes. This layer prevents the flow of the heat from our body to the cold surroundings and keeps our body relatively warmer.
Q6: In places of hot climate it is advised that outer walls of houses be painted white. Explain.
Ans: It is because the white colour reflects most of the heat that falls on it. Hence, the outer walls of the houses in the places of hot climate are advised to paint with white colour so that most of the heat falling on these walls would be reflected which will help in keeping the houses cool.
Q7: One liter of water at 300C is mixed with one liter of water at 500C. The temperature of the mixture will be:
Ans: d
Q8: An iron ball at 400C is dropped in a mug containing water at 400C. The heat will
Ans: b
Q9: A wooden spoon is dipped in a cup of ice cream. Its other end
Ans: d
Q10: Stainless steel pans are usually provided with copper bottoms. The reason for this could be that
Ans: c
1. What is heat and how is it related to temperature? |
2. How is heat transferred between objects? |
3. What are the effects of heat on different materials? |
4. How is heat measured? |
5. How can heat be controlled or manipulated? |
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