• Conduction in metals and non-metals - class-X
Back
0

Conduction in metals and non-metals - class-X

Description: conduction in metals and non-metals
Number of Questions: 26
Created by:
Tags: thermal energy transfers physics
Start the Quiz
Attempted 0/26 Correct 0 Score 0
‹
›

For cooking the food, which of the following type of utensil is most suitable 

conduction in metals and non-metals thermal energy transfers physics

  1. High specific heat and low conductivity

  2. High specific heat and high conductivity

  3. Low specific heat and low conductivity

  4. Low specific heat and high conductivity

Show answer
Correct Option: C

Two walls of thickness $d _1$ and $d _2$, thermal conductivities $K _1$ and $K _2$ are in contact. In the steady state if the temperature at the outer surfaces are $T _1$ and $T _2$, the temperature are the common wall will be 

conduction in metals and non-metals thermal energy transfers physics

  1. $\dfrac{K _1T _1+K _2T _2}{d _1d _2}$

  2. $\dfrac{K _1T _1d _2+K _2T _2d _1}{K _1d _2+K _2d _1}$

  3. $\dfrac{K _1d _1T _1+K _2d _2T _2}{K _1d _1+K _2d _2}$

  4. $\dfrac{(K _1d _1+K _2d _2)T _1T _2}{T _1+T _2}$

Show answer
Correct Option: B
Explanation:

$\begin{array}{l} { k _{ 1 } }\dfrac { { { T _{ 1 } }-{ T _{ c } } } }{ { { d _{ 1 } } } } ={ k _{ 2 } }\dfrac { { { T _{ c } }-{ T _{ 2 } } } }{ { { d _{ 2 } } } }  \ where\, { T _{ c } }\, is\, \, common\, \, wall\, temperature,\, solving\, for\, \, { T _{ c } }\, we\, \, will\, get \ { T _{ C } }=\dfrac { { { T _{ 1 } }+\alpha { T _{ 2 } } } }{ { \alpha +1 } }  \ u\sin  g\, \, \alpha =\dfrac { { { d _{ 1 } } } }{ { { d _{ 2 } } } } \dfrac { { { k _{ 2 } } } }{ { { k _{ 1 } } } }  \ { T _{ c } }=\dfrac { { { T _{ 1 } }+\dfrac { { { d _{ 1 } } } }{ { { d _{ 2 } } } } \dfrac { { { k _{ 2 } } } }{ { { k _{ 1 } } } } { T _{ 2 } } } }{ { \dfrac { { { d _{ 1 } } } }{ { { d _{ 2 } } } } \dfrac { { { k _{ 2 } } } }{ { { k _{ 1 } } } } +1 } }  \ =\dfrac { { { T _{ 1 } }\left( { { d _{ 2 } }{ k _{ 1 } } } \right) +{ T _{ 2 } }{ d _{ 1 } }{ k _{ 2 } } } }{ { { d _{ 1 } }{ k _{ 2 } }+{ d _{ 2 } }{ k _{ 1 } } } }  \ Hence,\, the\, option\, B\, is\, the\, \, correct\, answer. \end{array}$

The area of cross - section of rod is given by $ A = a _0 (1 + \alpha x )  $ where $  A _{ 0 }\quad & \quad \alpha  $ are constant and x is the distance from one end If thermal conductivity of material is K. What is the thermal resistance of the rod if its length is 

conduction in metals and non-metals thermal energy transfers physics

  1. $ KA _{ 0 }\alpha \quad to\quad (1+a\ell _{ 0 }) $

  2. $ \frac { 1 }{ Ka _{ 0 }\alpha } \quad \ell n \quad (1+\alpha\ell _{ 0 })$

  3. $ \frac { \alpha }{ KA _{ 0 } } \quad \ell n\quad (1+a\ell _{ 0 }) $

  4. $ \frac { KA _{ 0 } }{ \alpha } \ell n(1+\alpha \ell _{ 0 })$

Show answer
Correct Option: B
Explanation:

$\begin{array}{l} A={ a _{ 0 } }\left( { 1+\alpha x } \right)  \ dR=\dfrac { { dx } }{ { KA } }  \ =\dfrac { { dx } }{ { K{ \alpha _{ 0 } }\left( { 1+\alpha x } \right)  } }  \ =R=\dfrac { 1 }{ { K{ a _{ 0 } } } } \int _{ 0 }^{ { l _{ 0 } } }{ \dfrac { { dx } }{ { 1+\alpha x } }  }  \ =\dfrac { 1 }{ { \alpha K{ a _{ 0 } } } } \ln { \left( { 1+\alpha { l _{ 0 } } } \right)  }  \ =\dfrac { 1 }{ { K{ a _{ 0 } }\alpha  } } \ln { \left( { 1+\alpha { l _{ 0 } } } \right)  }  \ Hence, \ option\, \, B\, \, is\, correct\, \, answer. \end{array}$

a container that suits the occurrence of an isothermal process should be made of 

conduction in metals and non-metals thermal energy transfers physics

  1. Copper

  2. Glass

  3. Wood

  4. Cloth

Show answer
Correct Option: A

The temperature of skin is $T _{skin} = 34^0C$ (somewhat less than the body temperature, $T _{body} = 37^0C$) and the ambient tempreature is $T _{room} = 24^0C$. The surface area of an adult is A $\simeq$ 1.85 $m^2$. Calculate the net heat loss of the person.

conduction in metals and non-metals thermal energy transfers physics

  1. 25 W

  2. 100 W

  3. 300 W

  4. 500 W

Show answer
Correct Option: A

Consider a compound slab consisting of two different materials having equal thickness and thermals conductivities K and $2K$ in series. The equilvalent conductivity of  the slab is

conduction in metals and non-metals thermal energy transfers physics

  1. $\frac{2}{3}K$

  2. $\sqrt {2K} $

  3. $3K$

  4. $\left( {\frac{4}{3}} \right)K$

Show answer
Correct Option: C

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

Show answer
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. ${ 54 }^{ 0 }C$

Show answer
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

Show answer
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

Show answer
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. ${ 0 }^{ 0 }C$

Show answer
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. ${0^0}C.0K$

Show answer
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

Show answer
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. $\dfrac \pi2$

Show answer
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

Show answer
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

A heat engine takes steam at $200^oC$ and after doing work exhausts it directly into air at $100^oC$. Calculate the percentage of heat which is wasted.

conduction in metals and non-metals thermal energy transfers physics

  1. $58.86$

  2. $68.86$

  3. $48.86$

  4. $78.86$

Show answer
Correct Option: B

Which of the following material is most suitable for cooking utensil ?

conduction in metals and non-metals thermal energy transfers physics

  1. Low conductivity and low specific heat

  2. High conductivity and low specific heat

  3. Low conductivity and High specific heat

  4. High conductivity and High specific heat

Show answer
Correct Option: A

Two angular blocks A and B different metal have same length and same area of cross-section . they are kept in such a way that their cross-sectional area touch each other. the temperature at one end of A is $ 100^0 $ C and that of B at the other end is $0^0 C $ C . if the ratio of their conductivity is 1:3 then under steady state, the temperature of the junction in contact will be:-

conduction in metals and non-metals thermal energy transfers physics

  1. $ 25^0 C $

  2. $ 50^0 C $

  3. $ 75^0 C $

  4. $ 100^0 C $

Show answer
Correct Option: C

On heating one end of a rod, the temperature of the whole rod will be uniform when the :

conduction in metals and non-metals thermal energy transfers physics

  1. $k $ $ = 1$

  2. $k $ $ = 0$ 

  3. $k $ $ = 100$ 

  4. $k $ $ = \infty $

Show answer
Correct Option: D
Explanation:

If temperature of whole rod is same, it means that heat is being conducted from one end to other infinitely fast. This is possible only when thermal conductivity is infinite.

A slab consists of two parallel layers of two difference materials of same thickness and having thermal conductivities $K _1$ and $K _2$. The equivalent thermal conductivity K of the slab is-

conduction in metals and non-metals thermal energy transfers physics

  1. $K _1+K _2$

  2. $\frac{2K _1K _2}{K _1+K _2}$

  3. $\frac{K _1+K _2}{K _1K _2}$

  4. $K _1K _2$

Show answer
Correct Option: A

Which of the following represent practical uses each of good conductors of heat?

conduction in metals and non-metals thermal energy transfers physics

  1. Cooking vessels are coated with copper at the base so as to readily absorb heat energy and get the food cooked quickly, thus saving time and fuel

  2. Mercury is used as a thermometric liquid as it is a good conductor of heat

  3. Cooling coils of refrigerators and air-conditioners are made of copper as they easily conduct away the heat 

  4. None of the above

Show answer
Correct Option: A,B,C
Explanation:
Cooking vessel are coated with copper at base, so as to readily absorb heat and get food cooked quickly thus saving the fuel and time as copper is good conductor of heat and it has comparatively more thermal conductivity.

Mercury is used in thermometer as it is good conductor of heat; it expands on heating accordingly.

Cooling coils of refrigerators and air-conditioners are mode of copper as they easily conduct away the heat. As copper has high thermal conductivity; it absorbs heat more quickly and in that coils, coolants are present to absorb heat.

On a cold morning, a metal surface in touching is felt colder than a wooden surface, because the metal has:

conduction in metals and non-metals thermal energy transfers physics

  1. low thermal condutivity

  2. high thermal conductivity

  3. high specific heat

  4. low specific heat

Show answer
Correct Option: B
Explanation:

Metal appears cool on touching because heat flows from body (at higher temperature) to iron (at lower temperature). This can happen only when metal conducts heat. Wooden surface does not feel cool as it is non-conductor of heat.

On a cold morning, a metal surface will feel colder to touch than a wooden surface, because:

conduction in metals and non-metals thermal energy transfers physics

  1. metal has high specific heat

  2. metal has high thermal conductivity

  3. metal has low specific heat

  4. metal has low thermal conductivity

Show answer
Correct Option: B
Explanation:

The metal has high thermal conductivity, i.e., they conduct heat faster. and also metal is a good conductor of heat. Hence, it takes away your body heat as you touch it and which makes your body temperature to drop, therefore you feel the coldness when you touch a piece of metal.

Statement-1
On a chilly day, the metallic cap of a pen feels much colder than the plastic body although both are at the same (room) temperature.
Statement-2
Metal has a higher coefficient of thermal conductivity than plastic.

conduction in metals and non-metals thermal energy transfers physics

  1. Statement-1 is true, Statement-2 is true and Statement-2 is the correct explanation for Statement- 1

  2. Statement-1 is true, Statement-2 is true but Statement-2 is not the correct explanation for Staement-1

  3. Statement-1 is true, Statement-2 is false.

  4. Statement-1 is false, Statement-2 is true.

Show answer
Correct Option: A
Explanation:

On the chilly day the room temperature is lower than our body temperature.Since metal is better conductor than plastic when we touch the metal cap and the plastic body of a pen,heat from our finger will flow more to the metal body as compare to plastic body. Hence option (A) is correct.

Metals are good conductors of heat because.

conduction in metals and non-metals thermal energy transfers physics

  1. They contain large number of free electrons

  2. Their atoms are relatively apart.

  3. Their atoms collide frequently.

  4. They have reflecting surfaces.

Show answer
Correct Option: C
- Hide questions
ADVERTISEMENT

Find more quizzes from top tags

general knowledge
3615 Quizzes
119858 Questions
 technology
307 Quizzes
36705 Questions
 sports
963 Quizzes
19148 Questions
 history
1187 Quizzes
13475 Questions
 physics
598 Quizzes
13441 Questions
 biology
1160 Quizzes
12174 Questions
 science & technology
551 Quizzes
11015 Questions
 chemistry
490 Quizzes
9892 Questions
 maths
518 Quizzes
9324 Questions
 softskills
0 Quizzes
7131 Questions