Tag: physics

Questions Related to physics

Pick the odd one out. Give scientifc reason for your answer:

conduction in metals and non-metals thermal energy transfers physics

  1. Conduction, convection, fusion, radiation.

  2. Iron, aluminimum, asbestos, copper

  3. Felt, paper, silver, wood

  4. Ventilation, land breeze, sea breeze, thermos flask

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Correct Option: A
Explanation:

Conduction, convection and radiation are the mode of heat transfer whereas fusion is the nuclear reaction.

So, option A is correct.

It is required to double the pressure of a gas contained in steel cylinder by heating. If the initial temperature of the gas is ${ 27 }^{ 0 }C$, the temperature upto which it the gas is to be heated is 

conduction in metals and non-metals thermal energy transfers physics

  1. ${ 327 }^{ 0 }C$

  2. ${ 273 }^{ 0 }C$

  3. ${ 108}^{ 0 }C$

  4. ${ 54 }^{ 0 }C$

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Correct Option: C

At zero Kelvin, Germenium is:-

conduction in metals and non-metals thermal energy transfers physics

  1. Superconductor

  2. Good conductor

  3. Insulator

  4. Semiconductor

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Correct Option: C

A solid sphere and a hollow sphere of same material and size are heated to some temperature and allowed to cool in the same surroundings.If the temperature difference between each sphere and its surrounding is T, then:-

conduction in metals and non-metals thermal energy transfers physics

  1. The hollow sphere will cool at a faster rate for all values of T

  2. The solid sphere will cool at a faster rate for all values of T

  3. Both spheres will coll at the same rate for all values of T

  4. Both spheres will coll at the same rate only for small values of T

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Correct Option: C

Two identical bodies are made of a material for which the heat capacity increases with temperature. One of these is at ${ 100 }^{ 0 }$, while the other one is at ${ 0 }^{ 0 }C$. If the two bodies are brought into contact, then assuming no heat loss, the final common temperature is

conduction in metals and non-metals thermal energy transfers physics

  1. ${ 50 }^{ 0 }C$

  2. more than ${ 50 }^{ 0 }C$

  3. less than ${ 50 }^{ 0 }C$ but greater than ${ 0 }^{ 0 }C$

  4. ${ 0 }^{ 0 }C$

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Correct Option: A

When a thermometer is taken from the melting ice to a warm liquid, the mercury level rises to two-fifths of the distance between the lower and the upper fixed points. Find the temperature of the liquid $(i)i{n^o}C,and(ii)\;in\;K.$ 

conduction in metals and non-metals thermal energy transfers physics

  1. ${40^0}C.313K$

  2. ${30^0}C.227K$

  3. ${20^0}C.273K$

  4. ${0^0}C.0K$

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Correct Option: A

In winter , temprature of bottom of take is 4$$C . Ratio of thermal conductance of ice and water is 2:3 and depth of the take 20 m. Find the maximum thickness os ice formed .  

conduction in metals and non-metals thermal energy transfers physics

  1. $\frac { 200 }{ 11 } M$

  2. $\frac { 100 }{ 8 } M$

  3. $\frac { 220 }{ 12 } M$

  4. 10 M

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Correct Option: C

A semicircular rod is joined at its end to a straight rod of the same material and the same cross-sectional area. The straight rod forms a diameter of the other rod. The junctions are maintained at different temperatures. Find the ratio of the heat transferred through a cross-section of the semicircular rod of the heat transferred through a cross-section the straight rod in the given time.

conduction in metals and non-metals thermal energy transfers physics

  1. $\dfrac 2\pi$

  2. $\dfrac 1\pi$

  3. $\dfrac 1{2\pi}$

  4. $\dfrac \pi2$

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Correct Option: A

Bimetallic thermostat consists two metals of different thermal co-efficient thermostat always bends towards material having
(i)large thermal expansion on heating 
(ii)large thermal expansion on cooling
(iii)small thermal expansion on heating
(iv)small thermal expansion on cooling

conduction in metals and non-metals thermal energy transfers physics

  1. I only

  2. II only

  3. III and II only

  4. I and IV only

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Correct Option: C

The ratio of radii of two spheres of same material is  $1:4 .$  Then the ratio of their heat  capacity will be

conduction in metals and non-metals thermal energy transfers physics

  1. $\dfrac { 1 } { 64 }$

  2. $\dfrac { 1 } { 32 }$

  3. $\dfrac { 1 } { 2 }$

  4. $\dfrac { 1 } { 4 }$

Show answer
Correct Option: C