NEET > Properties of Bulk Matter

Explore popular questions from Properties of Bulk Matter for NEET. This collection covers Properties of Bulk Matter previous year NEET questions hand picked by popular teachers.


Q 1.    

Correct4

Incorrect-1

The total radiant energy per unit area, normal to the direction of incidence, received at a distance {tex} R {/tex} from the centre of a star of radius {tex} r , {/tex} whose outer surface radiates as a black body at a temperature {tex} T K {/tex} is given by: {tex} ( \sigma \text { is Stefan's } {/tex} constant)

{tex} \frac { \sigma r ^ { 2 } T ^ { 4 } } { R ^ { 2 } } {/tex}

B

{tex} \frac { \sigma r ^ { 2 } T ^ { 4 } } { 4 \pi r ^ { 2 } } {/tex}

C

{tex} \frac { \sigma r ^ { 4 } T ^ { 4 } } { r ^ { 4 } } {/tex}

D

{tex} \frac { 4 \pi \sigma r ^ { 2 } T ^ { 4 } } { R ^ { 2 } } {/tex}

Explanation

Q 2.    

Correct4

Incorrect-1

Three rods of same dimensions are arranged as shown in figure, have thermal conductivities {tex} \mathrm { K } _ { 1 } , \mathrm { K } _ { 2 } {/tex} and {tex} \mathrm { K } _ { 3 } {/tex} . The points {tex} \mathrm { P } {/tex} and {tex} \mathrm { Q } {/tex} are maintained at different temeratures for the heat to flow at the same rate along {tex} \mathrm { PRQ } {/tex} and {tex} \mathrm { PQ } {/tex} . Then which of the following option is correct?

A

{tex} K _ { 3 } = \frac { 1 } { 2 } \left( K _ { 1 } + K _ { 2 } \right) {/tex}

B

{tex} K _ { 3 } = K _ { 1 } + K _ { 2 } {/tex}

{tex} K _ { 3 } = \frac { K _ { 1 } K _ { 2 } } { K _ { 1 } + K _ { 2 } } {/tex}

D

{tex} K _ { 3 } = - 2 \left( K _ { 1 } + K _ { 2 } \right) {/tex}

Explanation





Q 3.    

Correct4

Incorrect-1

The sprinkling of water slightly reduces the temperature of a closed room because

A

temperature of water is less than that of the room

B

specific heat of water is high

water has large latent heat of vaporisation

D

water is a bad conductor of heat

Explanation



Q 4.    

Correct4

Incorrect-1

The value of molar heat capacity at constant temperature is

A

zero

infinity

C

unity

D

4.2

Explanation

Q 5.    

Correct4

Incorrect-1

The specific heat capacity of a metal at low temperature (T) is given as
{tex} C _ { p } \left( k J K ^ { - 1 } \mathrm { kg } ^ { - 1 } \right) = 32 \left( \frac { T } { 400 } \right) ^ { 3 } {/tex}
A 100 gram vessel of this metal is to be cooled from {tex} 20 ^ { \circ } \mathrm { K } {/tex} to {tex} 4 ^ { \circ } \mathrm { K } {/tex} by a special refrigerator operating at room temperature {tex} \left( 27 ^ { \circ } \mathrm { C } \right) . {/tex} The amount of work required to cool the vessel is

A

greater than 0.148 {tex} \mathrm { kJ } {/tex}

B

between 0.148 {tex} \mathrm { kJ } {/tex} and 0.028 {tex} \mathrm { kJ } {/tex}

C

less than 0.028 {tex} \mathrm { kJ } {/tex}

equal to 0.002 {tex} \mathrm { kJ } {/tex}

Explanation



Q 6.    

Correct4

Incorrect-1

The emissive power of a black body at {tex} \mathrm { T } = 300 \mathrm { K } {/tex} is 100{tex} \mathrm { Watt } / {/tex} {tex} \mathrm { m } ^ { 2 } . {/tex} Consider a body {tex} \mathrm { B } {/tex} of area {tex} \mathrm { A } = 10 \mathrm { m } ^ { 2 } {/tex} coefficient of reflectivity {tex} \mathrm { r } = 0.3 {/tex} and coefficient of transmission {tex} \mathrm { t } = 0.5 . {/tex} Its temperature is 300{tex} \mathrm { K } {/tex} . Then which of the following is incorrect?

A

The emissive power of {tex} \mathrm { B } {/tex} is 200{tex} \mathrm { W } / \mathrm { m } ^ { 2 } {/tex}

The emissive power of {tex} \mathrm { B } {/tex} is 20{tex} \mathrm { W } / \mathrm { m } ^ { 2 } {/tex}

C

The power emitted by {tex} \mathrm { B } {/tex} is 200 Watts

D

The emissivity of {tex} \mathrm { B } {/tex} is 0.2

Explanation

Q 7.    

Correct4

Incorrect-1

A solid cube and a solid sphere of the same material have equal surface area. Both are at the same temperture {tex} 120 ^ { \circ } \mathrm { C } {/tex} , then

A

both the cube and the sphere cool down at the same rate

the cube cools down faster than the sphere

C

the sphere cools down faster than the cube

D

whichever is having more mass will cool down faster

Explanation



Q 8.    

Correct4

Incorrect-1

The density of water at {tex} 20 ^ { \circ } \mathrm { C } {/tex} is 998{tex} \mathrm { kg } / \mathrm { m } ^ { 3 } {/tex} and at {tex} 40 ^ { \circ } \mathrm { C } \ 992 {/tex} {tex} \mathrm { kg } / \mathrm { m } ^ { 3 } . {/tex} The coefficient of volume expansion of water is

A

{tex} 10 ^ { - 4 / {^ \circ }} \mathrm { C } {/tex}

{tex} 3 \times 10 ^ { - 4 / ^ { \circ } }\mathrm { C } {/tex}

C

{tex} 2 \times 10 ^ { - 4 } / ^ { \circ } \mathrm { C } {/tex}

D

{tex} 6 \times 10 ^ { - 4 } / ^ { \circ } \mathrm { C } {/tex}

Explanation



Q 9.    

Correct4

Incorrect-1

A metallic rod {tex} \ell \mathrm { cm } {/tex} long, {tex} \mathrm { A } {/tex} square {tex} \mathrm { cm } {/tex} in cross-section is heated through {tex} \mathrm { t } ^ { \circ } \mathrm { C } {/tex} . If Young's modulus of elasticity of the metal is {tex} \mathrm { E } {/tex} and the mean coefficient of linear expansion is {tex} \alpha {/tex} per degree celsius, then the compressional force required to prevent the rod from expanding along its length is

{tex} \mathrm { E }\, \mathrm { A } \,\alpha \,\mathrm { t } {/tex}

B

E A {tex} \alpha {/tex} t/ {tex} ( 1 + \alpha t ) {/tex}

C

E A {tex} \alpha {/tex} t/ {tex} ( 1 - \alpha \text { t) } {/tex}

D

{tex} \mathrm { E } \ell \alpha \mathrm { t } {/tex}

Explanation

Q 10.    

Correct4

Incorrect-1

If liquefied oxygen at 1 atmospheric pressure is heated from 50{tex} \mathrm { K } {/tex} to 300{tex} \mathrm { K } {/tex} by supplying heat at constant rate. The graph of temperature vs time will be

A

B

D

Explanation

Q 11.    

Correct4

Incorrect-1

If a bar is made of copper whose coefficient of linear expansion is one and a half times that of iron, the ratio of force developed in the copper bar to the iron bar of identical lengths and cross-sections, when heated through the same temperature range (Young's modulus of copper may be taken to be equal to that of iron) is

{tex}3 / 2 {/tex}

B

{tex}2 / 3 {/tex}

C

{tex}4/ 9 {/tex}

D

{tex} 4/ 9 {/tex}

Explanation

Q 12.    

Correct4

Incorrect-1

A piece of ice falls from a height h so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h is: {tex} \left. \text { [Latent heat of ice is } 3.4 \times 10 ^ { 5 } \mathrm { J } / \mathrm { kg } = 10 \mathrm { N } / \mathrm { kg } \right] {/tex}

A

34{tex} \mathrm { km } {/tex}

B

544{tex} \mathrm { km } {/tex}

136{tex} \mathrm { km } {/tex}

D

68{tex} \mathrm { km } {/tex}

Explanation



Q 13.    

Correct4

Incorrect-1

A body of mass 5{tex} \mathrm { kg } {/tex} falls from a height of 20 metres on the ground and it rebounds to a height of {tex} 0.2 \mathrm { m } . {/tex} If the loss in potential energy is used up by the body, then what will be the temperature rise?
(specific heat of material = {tex}\mathrm{0.09\,cal\,gm^{-1} {^\circ} C ^{-1}}{/tex})

A

{tex} 0 ^ { \circ } \mathrm { C } {/tex}

B

{tex} 4 ^ { \circ } \mathrm { C } {/tex}

C

{tex} 8 ^ { \circ } \mathrm { C } {/tex}

None of these

Explanation



Q 14.    

Correct4

Incorrect-1

Two straight metallic strips each of thickness t and length {tex} \ell {/tex} are rivetted together. Their coefficients of linear expansions are {tex} \alpha _ { 1 } {/tex} and {tex} \alpha _ { 2 } {/tex} . If they are heated through temperature {tex} \Delta \mathrm { T } {/tex} , the bimetallic strip will bend to form an arc of radius

A

{tex} \left.t / \left\{ \alpha _ { 1 } + \alpha _ { 2 } \right) \Delta \mathrm { T } \right\} {/tex}

{tex} \mathrm { t } / \left\{ \left( \alpha _ { 2 } - \alpha _ { 1 } \right) \Delta \mathrm { T } \right\} {/tex}

C

{tex} \mathrm { t } \left( \alpha _ { 1 } - \alpha _ { 2 } \right) \Delta \mathrm { T } {/tex}

D

{tex} t \left( \alpha _ { 2 } - \alpha _ { 1 } \right) \Delta T {/tex}

Explanation

Q 15.    

Correct4

Incorrect-1

The figure shows a system of two concentric spheres of radii {tex} r _ { 1 } {/tex} and {tex} r _ { 2 } {/tex} are kept at temperatures {tex} T _ { 1 } {/tex} and {tex} ^ { 2 } T _ { 2 } {/tex} ,
respectively. The radial rate of flow heat in a substance between the two concentric spheres is proportional to

A

{tex} \ell n \left( \frac { r _ { 2 } } { n } \right) {/tex}

B

{tex} \frac { \left( r _ { 2 } - r _ { 1 } \right) } { \left( r _ { 1 } r _ { 2 } \right) } {/tex}

C

{tex} \left( r _ { 2 } - r _ { 1 } \right) {/tex}

{tex} \frac { r _ { 1 } r _ { 2 } } { \left( r _ { 2 } - r _ { 1 } \right) } {/tex}

Explanation







Q 16.    

Correct4

Incorrect-1

A block of steel heated to {tex} 100 ^ { \circ } \mathrm { C } {/tex} is left in a room to cool. Which of the curves shown in fig., represents the correct behaviour?

{tex} \mathrm { A } {/tex}

B

{tex} B {/tex}

C

{tex} C {/tex}

D

None of these

Explanation

Q 17.    

Correct4

Incorrect-1

Which of the following will expand the most for same rise in temperature?

Aluminium

B

Glass

C

Wood

D

All will expand same

Explanation

Q 18.    

Correct4

Incorrect-1

The plots of intensity versus wavelength for three black bodies at temperatures {tex} T _ { 1 } , T _ { 2 } {/tex} and {tex} T _ { 3 } {/tex} respectively are as shown. Their temperature are such that

A

{tex} T _ { 1 } > T _ { 2 } > T _ { 3 } {/tex}

{tex} T _ { 1 } > T _ { 3 } > T _ { 2 } {/tex}

C

{tex} T _ { 2 } > T _ { 3 } > T _ { 1 } {/tex}

D

{tex} T _ { 3 } > T _ { 2 } > T _ { 1 } {/tex}

Explanation

Q 19.    

Correct4

Incorrect-1

When the temperature of a rod increases from t to t {tex} + \Delta \mathrm { t } {/tex} , its moment of inertia increases from {tex}I{/tex} to {tex} \mathrm { I } + \Delta \mathrm { I } {/tex} . If {tex} \alpha {/tex} be the< coefficient of linear expansion of the rod, then the value of {tex} \frac { \Delta \mathrm { I } } { \mathrm { I } } {/tex} is

2{tex} \alpha \triangle t {/tex}

B

{tex} \alpha \Delta \mathrm { T } {/tex}

C

{tex} \frac { \alpha \Delta t } { 2 } {/tex}

D

{tex} \frac { \Delta \mathrm { t } } { \alpha } {/tex}

Explanation



Q 20.    

Correct4

Incorrect-1

Two rods, one of aluminum and the other made of steel, having initial length {tex} \ell _ { 1 } {/tex} and {tex} \ell _ { 2 } {/tex} are connected together to form a single rod of length {tex} \ell _ { 1 } + \ell _ { 2 } . {/tex} The coefficients of linear
expansion for aluminum and steel are {tex} \alpha _ { a } {/tex} and {tex} \alpha _ { s } {/tex} and respectively. If the length of each rod increases by the same
amount when their temperature are raised by {tex} t ^ { 0 } \mathrm { C } , {/tex} then find the ratio {tex} \ell _ { 1 } / \left( \ell _ { 1 } + \ell _ { 2 } \right) {/tex}

A

{tex} \alpha_s / \alpha_a {/tex}

B

{tex} \alpha _ { a } / \alpha _ { s } {/tex}

{tex} \alpha_s / \left( \alpha _ { a } + \alpha _ { s } \right) {/tex}

D

{tex} \alpha _ { a } / \left( \alpha _ { a } + \alpha _ { s } \right) {/tex}

Explanation

Q 21.    

Correct4

Incorrect-1

A polished metal plate with a rough black spot on it is heated to about 1400{tex} \mathrm { K } {/tex} and quickly taken into a dark room. Which one of the following statements will be true?

The spot will appear brighter than the plate

B

The spot will appear darker than the plate

C

The spot and piate will appear equally bright

D

The spot and the plate will not be visible in the dark room

Explanation

Q 22.    

Correct4

Incorrect-1

On observing light from three different stars {tex} \mathrm { P } , \mathrm { Q } {/tex} and {tex} \mathrm { R } {/tex} , it was found that intensity of violet colour is maximum in the spectrum of {tex} \mathrm { P } {/tex} , the intensity of green colour is maximum in the spectrum of R and the intensity of red colour is maximum in the spectrum of Q. If {tex}T_{p},\, T _ { Q } {/tex} and {tex} T _ { R } {/tex} are the respective absolute temperature of {tex} P , Q {/tex} and {tex} R , {/tex} then it can be concluded from the above observations that

{tex} \mathrm { T } _ { \mathrm { p } } > \mathrm { T } _ { \mathrm { R } } > \mathrm { T } _ { \mathrm { Q } } {/tex}

B

{tex} \mathrm { T } _ { \mathrm { p } } < \mathrm { T } _ { \mathrm { R } } < \mathrm { T } _ { \mathrm { Q } } {/tex}

C

{tex} \mathrm { T } _ { \mathrm { p } } < \mathrm { T } _ { \mathrm { Q } } < \mathrm { T } _ { \mathrm { R } } {/tex}

D

{tex} \mathrm { T } _ { \mathrm { P } } > \mathrm { T } _ { \mathrm { Q } } ^ { } > \mathrm { T } _ { \mathrm { R } } ^ { } {/tex}

Explanation

Q 23.    

Correct4

Incorrect-1

A partition wall has two layers of different materials {tex} A {/tex} and {tex} B {/tex} in contact with each other. They have the same thickness but the thermal conductivity of layer {tex} A {/tex} is twice that of layer B. At steady state the temperature difference across the layer {tex} B {/tex} is 50{tex} \mathrm { K } {/tex} , then the corresponding difference across the layer {tex} \mathrm { A } {/tex} is

A

50{tex} \mathrm { K } {/tex}

B

12.5{tex} \mathrm { K } {/tex}

25{tex} \mathrm { K } {/tex}

D

60{tex} \mathrm { K } {/tex}

Explanation





Q 24.    

Correct4

Incorrect-1

Which of the following statements is/are false about mode of heat transfer?

A

In radiation, heat is transfered from one medium to another without affecting the intervening medium

Radiation and convection are possible in vaccum while conduction requires material medium.

C

Conduction is possible in solids while convection occurs in liquids and gases.

D

All are correct

Explanation

Q 25.    

Correct4

Incorrect-1

In a vertical U-tube containing a liquid, the two arms are maintained at different temperatures {tex} t _ { 1 } {/tex} and {tex} t _ { 2 } {/tex} . The liquid columns in the two arms have heights {tex} l _ { 1 } {/tex} and {tex} l _ { 2 } {/tex} respectively. The coefficient of volume expansion of the liquid is equal to

{tex} \frac { l _ { 1 } - l _ { 2 } } { l _ { 2 } t _ { 1 } - l _ { 1 } t _ { 2 } } {/tex}

B

{tex} \frac { l _ { 1 } - l _ { 2 } } { l _ { 1 } t _ { 1 } - l _ { 2 } t _ { 2 } } {/tex}

C

{tex} \frac { l _ { 1 } + l _ { 2 } } { l _ { 2 } t _ { 1 } + l _ { 1 } t _ { 2 } } {/tex}

D

{tex} \frac { l _ { 1 } + l _ { 2 } } { l _ { 1 } t _ { 1 } + l _ { 2 } t _ { 2 } } {/tex}

Explanation