QUESTIONS
I.FILL IN THE
BLANK SPACES BY CHOOSING CORRECT WORDS FROM THE LIST GIVEN BELOW:
List:
rollers, air, poor, solids, cubical, conduction,
melting,sublime,condensation,expands,
1.
Convection cannot take place
in-----------------------
2.
The Liquids and gases have
only------------------------
3.
Bridges are mounted on ------------------------
to prevent their collapse.
4.
Shining bodies are --------------------------
absorbers of radiant heat.
5.
Radiant heat can easily pass through
-------------------------------------------.
6.
A fixed temperature at which a solid changes
into a liquid state is called ------------------------
Point.
7.
The process due to which a gas changes into a
liquid state a t fixed temperature is called
---------------------------------
8.
A gaseous form of solid formed directly on
heating is called -------------------
9.
Alcohol -------------------------- more than
mercury.
10.
Solids get heated only by ---------------------------------------
II. Choose
the most appropriate answer.
1. Heat energy produces a
sensation of
a)Warmth b) coldness c) both warmth and coldness d) none of these
2. During a day time the air
becomes warm due to the process of
a) conduction b)
Convection c) radiation d) expansion
3. A loose woollen cloth keeps us
warm in summer, because:
a) it produces large
amount of heat
b) it prevents heat radiation from body by
conduction
c) it prevents heat
radiation from body by convection
d) it prevents heat
radiation from body by radiation
4. Fastest mode of transmission of
heat is
a) Conduction b)
convection c) radiation d) None of these
5.
Black surface are:
a) good absorbers of heat
only
b) good radiators of heat
only
c) Poor absorbers of heat
d) good absorbers and good
radiators of heat
6. A bimetallic strip is made of
iron and Brass : when heated in a flame
a) the iron expands more
than Brass
b) the brass expands more than iron
c) both iron and brass
expands equal
d) none of these
7. The only liquid at room
temperature in which conduction is possible, is
a) water b) benzene c)
alcohol d)mercury
8. A device in which heat losses are
minimized due to conduction ,convection and radiation is
a) thermometer b) bimetallic
strip c) thermos flask d) solar cooker