## Tuesday, June 4, 2013

### CBSE Class 7 - Science - CH4 - Heat (MCQs)

Heat & Temperature
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MCQs

Q1: When matter gets warmer, the atoms and molecules in that matter __________________

(a) stand still
(b) move faster
(c) move slower
(d) can't say

Q2: Higher the temperature of the body _____ is the kinetic energy of the molecules of that body?

(a) higher
(b) lower
(c) same
(d) none of these

Q3(NCERT): Stainless steel pans are usually provided with copper bottoms. The reason for this could be that

(a) copper bottom makes the pan more durable.
(b) such pans appear colourful.
(c) copper is a better conductor of heat than the stainless steel.
(d) copper is easier to clean than the stainless steel.

Q4: Unit of heat energy is
(a) kilogram
(b) metre
(c) joule
(d) degree

Q5(NCERT): One litre of water at 30°C is mixed with one litre of water at 50°C. The temperature of the 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

Q6: Bodies transmitting heat via radiation

(a) do not require any medium
(b) are liquids only
(c) make heat travels in one direction only.
(d) solids only.

Q7: In Fahrenheit scale, water freezes at

(a) 0° F
(b) 32° F
(c) 40° F
(d) 212° F

Q8(NCERT): 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.

Q9: Boiling point of water is
(a) 0° C
(b) 100° C
(c) 357° C
(d) -39°C

Q10: A Thermos flask prevents loss or gain of heat by
(a) conduction only
(b) convection only
(d) all the above

Q11(NCERT): A wooden spoon is dipped in a cup of ice cream. Its other end
(a) becomes cold by the process of conduction.
(b) becomes cold by the process of convection.
(c) becomes cold by the process of radiation.
(d) does not become cold.

Q12: Sea breeze is caused due to

(a) conduction
(b) convection
(d) all of these

Q13: A polished silvery surface is
(a) good absorber of heat
(b) good reflector of heat
(c) poor reflector of heat
(d) None of these

Q14: Device used for measuring temperatures is called a
(a) Barometer
(b) Odometer
(c) Thermometer
(d) Speedometer

1: (b) move faster
2: (a) higher
3: (c) copper is a better conductor of heat than the stainless steel.
4: (c) joule
5: (d) between 30°C and 50°C
6: (a) do not require any medium
7: (b) 32° F
8: (b) not flow from iron ball to water or from water to iron ball.
9: (b) 100° C
10: (d) all the above
11: (d) does not become cold.
12: (b) convection
13: (b) good reflector of heat
14: (c) Thermometer