Last updated on August 30th, 2023 at 12:59 am
NCERT Solutions Class 7 Science Chapter 4 Heat
Class 7 Science Chapter 4 Heat Question Answer by online-shiksha
Q1 : State similarities and differences between the laboratory thermometer andthe clinical thermometer.
Answer :
Similarities:
Both thermometers have long narrow glass tubes.
Both thermometers have mercury in their bulbs.
Differences:
Clinical thermometers range from 35°C to 42°C | laboratory thermometers range from -10°C to 110°C. |
Clinical thermometers are used to check the body’s temperature | Lab thermometers cannot measure human body temperature. |
clinical thermometers that can be tilted. | Laboratory thermometers are generally upright while reading the temperature |
Q2 : Give two examples each of conductors and insulators of heat.
Answer :
Two examples of conductors of heat are:Â Aluminium & Â Iron
Two examples of insulators of heat are:Â Wood & Plastic
Q3 :Â Fill in the blanks:
- The hotness of an object is determined by its __ __.Â
- Temperature of boiling water cannot be measured by a ____ thermometer.
- Temperature is measured in degree ___ _.
- No medium is required for transfer of heat by the process of ___ _.
- A cold steel spoon is dipped in a cup of hot milk. It transfers heat to its other end by the process of __ _ _.
- Clothes of ___ _ colours absorb heat better than clothes of light colours.
Answer :
- Temperature
- Clinical Thermometer.
- Celsius
- Radiation
- Conduction
- Dark
Q4 :Â Match the following:Â
1. Land breeze blows during | a. Summer |
2. Sea breeze blows during | b. Winter |
3. Dark coloured clothes are preferred during | c. Day |
4. Light coloured clothes are preferred during | d. Night |
Answer :Â
-  Night , 2. Day , 3. Winter , 4. Summer
Q5 : Discuss why wearing more layers of clothing during winters keeps us warmer than wearing just one thick piece of clothing.
Answer :
In the winter, wearing more layers of clothing keeps us warmer than wearing one piece since air gets trapped between them. Since air is an insulator of heat, it keeps us warm and prevents the body from losing heat. Layers of clothing keep us warm.