Class 7 Science Chapter 3 Practice Question Answers - Heat

Q1. Heat in liquid travels from the:
(a) bottom to top
(b) top to bottom
(c) right to left
(d) left to right
Ans: (a)
Heat in liquid travels from bottom to top.

Q2. Heat transferred into solids by:
(a) conduction
(b) convection
(c) radiation
(d) insulators
Ans: (a)
Heat transferred into solids by conduction.

Q3. The substances which conduct heat easily are called:
(a) convection
(b) radiation
(c) conductors
(d) none of these
Ans: (c)
The substances which conduct heat easily is called conductor.

Q4. In which process heat is transferred from hotter end to colder end is known as:
(a) conduction
(b) convection
(c) radiation
(d) none of these
Ans: (a)
Heat is transferred from hotter end to colder end is known as conduction.

Q5. The substances which do not conduct heat easily are called:
(a) insulators
(b) convection
(c) conductors
(d) none of these
Ans: (a)
Insulators do not conduct heat easily.

Q6. In which process the liquid itself moves and carries the heat from one place to another ?
(a) radiation
(b) conductors
(c) convection
(d) none of these
Ans: (c)
In convection liquid itself moves and carries the heat from one place to another.

Q7. The correct method of reading a clinical thermometer is:
(a) holding the thermometer by bulb
(b) before use the mercury level should be below 39°C
(c) don’t hold the thermometer by bulb
(d) none of these
Ans: (c)
Don’t hold the thermometer by the bulb while reading it.

Q8. The normal temperature of human body is:
(a) 47°C
(b) 36°C
(c) 37°C
(d) 39°C
Ans: (c)
The normal temperature of human body is 37°C.

Q9. Which currents are formed in all liquid on heating ?
(a) radiation current
(b) conduction current
(c) convection current
(d) none of these
Ans: (c)
Convection currents are formed in all liquid on heating.

Q10. The hand which is over the flame feels hotter because hot air moves in:
(a) downward direction
(b) upward direction
(c) circular direction
(d) none of these
Ans: (b)
The hand feels hotter because air moves upward direction.

Q11. Which thermometer is used to measure temperature of different things and places ?
(a) Laboratory thermometer
(b) Clinical thermometer
(c) Minimum and maximum thermometer
(d) None of these
Ans: (a)
Laboratory thermometer measure the temperature of things and places.

Q12. The range of laboratory thermometer is:
(a) 70°C to 110°C
(b) -10°C to 110°C
(c) 20°C to 110°C
(d) None of these
Ans: (b)
-10°C to 110°C is the range of laboratory thermometer.

Q13. Which scale is used in clinical thermometer nowadays ?
(a) Celsius scale
(b) Fahrenheit scale
(c) Both (a) and (b)
(d) None of these
Ans: (a)
Celsius scale is used in clinical thermometer nowadays.

Q14. Which scale was used in clinical thermometer during earlier times?
(a) Celsius scale
(b) Fahrenheit scale
(c) Both (a) and (b)
(d) None of these
Ans: (b)
Fahrenheit scale was used in clinical thermometer during earlier time.

Q15. Which thermometer records the highest and lowest temperature during a period of time ?
(a) Clinical thermometer
(b) Laboratory thermometer
(c) Minimum and maximum thermometer
(d) None of these
Ans: (c)
Minimum and maximum temperature records temperature of time.

Q16. A thermometer which do not use mercury is known as:
(a) clinical thermometer
(b) laboratory thermometer
(c) digital thermometer
(d) none of these
Ans: (c)
Digital thermometer do not use mercury.

Q17. The scale used with the laboratory thermometer is Celsius scale, indicated by:
(a) °F
(b) °C
(c) K
(d) None of these
Ans: (c)
Celcius scale is indicated by °C.

Q18. One litre of water at 30°C is mixed with one litre of water at 50°C. The temperature of mixture  will be:
(a) 80°C
(b) More than 50°C but less than 80°C
(c) 20°C
(d) Between 30°C and 50°C
Ans: (d)
Between 30°C and 50°C because temperature of mixture will be between.

Q19. An iron ball at 40°C is dropped in a mug containing water at 40°C. The heat will:
(a) flow from iron ball to water
(b) not flow from iron ball to water or from water to iron ball
(c) flow from water to iron ball
(d) increase the temperature of both
Ans: (b)
The heat will not flow from iron ball to water or from water to ball.

Q20. A wooden spoon is dipped in a cup of ice-cream its other end:
(a) becomes cold by the process of convection
(b) becomes cold by the process of conduction
(c) becomes cold by the process of radiation
(d) does not become cold
Ans: (d)
Its other end does not become cold.

Q21. Stainless steel pans are usually provided with copper bottom. The reason for this could be that:
(a) copper bottom makes the pan more durable
(b) such pans appear colourful
(c) copper is easier to clean than stainless steel
(d) copper is a better conductor of heat than the stainless steel
Ans: (d)
Copper is a better conductor of heat than the stainless steel.

Q22. The process by which we get heat while sitting in front of a room heater is :
(a) conduction
(b) convection
(c) radiation
(d) none of these
Ans: (c)
The process by which we get heat is radiation.

Q23. To measure the temperature of an object, we use:
(a) Barometer
(b) Lactometer
(c) Thermometer
(d) None of these
Ans: (c)
Thermometer is used to measure the temperature of an object.

Q24. Which of the following substance is a bad conductor of heat ?
(a) Steel
(b) Gold
(c) Wood
(d) Silver
Ans: (c)
Wood is a bad conductor of heat.

Q25. Which of the following substance is not a bad conductor of heat ?
(a) Rubber
(b) Aluminium
(c) Glass
(d) Plastic
Ans: (b)
Aluminium is not a bad conductor of heat.

Q26. The transfer of heat by conduction is in:
(a) solids
(b) liquids
(c) gases
(d) none of these
Ans: (a)
The transfer of heat by conduction is in solids.

Q27. Which of the following colour absorb maximum heat ?
(a) White
(b) Black
(c) Blue
(d) Pink
Ans: (b)
Black colour absorb maximum heat.

Q28. Convection currents are formed in:
(a) solids
(b) liquids
(c) gases
(d) none of these
Ans: (b)
Convection currents are formed in liquids.

Q29. The phenomenon involved in the formation of land and sea breeze is:
(a) conduction
(b) convection
(c) radiation
(d) all of these
Ans: (b)
The phenomenon involved in the formation of land and sea breeze is convection.

Q30. Which of the following would expand most on being heated for some time ?
(a) Air
(b) Water
(c) Iron
(d) All of these
Ans: (a)
Air would expand most on being heated for some time.