The ratio of the coefficient of thermal conductivity of two different materials is 5 : 3. If the thermal resistance of the rod of same thickness resistance of the rods of same thickness of these materials is same, then the ratio of the length of these rods will be
(a) 3 : 5                    (b) 5 : 3
(c) 3 : 4                    (d) 3 : 2

Concept Questions :-

Conduction
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Difficulty Level:

Which of the following circular rods (given radius r and length l) each made of the same material as whose ends are maintained at the same temperature will conduct most heat ?

(a)             (b)
(c)                 (d)

Concept Questions :-

Conduction
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

It is hotter for the same distance over the top of a fire than it is in the side of it, mainly because

(a) Air conducts heat upwards

(c) Convection takes more heat upwards

(d) Convection, conduction and radiation all contribute significantly transferring heat upwards

Concept Questions :-

Convection
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

One likes to sit under sunshine in winter season, because

(a) The air surrounding the body is hot by which body gets heat

(b) We get energy by sun

(c) We get heat by conduction by sun

(d) None of the above

Concept Questions :-

Conduction
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Air is bad conductor of heat or partly conducts heat, still vacuum is to be placed between the walls of the thermos flask because

(a) It is difficult to fill the air between the walls of thermos flask

(b) Due to more pressure of air, the thermos can get crack

(c) By convection, heat can flow through air

(d) On filling the air, there is no advantage

Concept Questions :-

Convection
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

While measuring the thermal conductivity of a liquid, we keep the upper part hot and lower part cool, so that

(a) Convection may be stopped

(c) Heat conduction is easier downwards

(d) It is easier and more convenient to do so

Concept Questions :-

Convection

Difficulty Level:

Mode of transmission of heat, in which heat is carried by the moving particles, is
(c) Convection         (d) Wave motion

Concept Questions :-

Convection
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

In heat transfer, which method is based on gravitation ?

(a) Natural convection               (b) Conduction
(c) Radiation                             (d) Stirring of liquids

Concept Questions :-

Convection
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

When fluids are heated from the bottom, convection currents are produced because -

(a) Molecular motion of fluid becomes aligned

(b) Molecular collisions take place within the fluid

(c) Heated fluid becomes more dense than the cold fluid above it

(d) Heated fluid becomes less dense than the cold fluid above it

Concept Questions :-

Convection

Difficulty Level:

If a liquid is heated in weightlessness, the heat is transmitted through

(a) Conduction

(b) Convection