140 + Interview Questions in THERMOMETRY IN GENERAL AWARENESS Page 2 InterviewSolution

51.	An iron ball has a diameter of `6 cm` and is `0.010 mm` too large to pass through a hole in a brass plate when the ball and plate are at a temperature of `30^@ C`. At what temperature, the same for ball and plate, will the ball just pass through the hole? Take the values of (prop) from Table `20 .2`.
Answer» Correct Answer - C `Delta d = d(alpha_B - alpha_(Fe)) Delta theta` :. `Delta theta = (Delta d)/(d(alpha _B -alpha_(Fe))` = `(0.01)/(60 xx 0.8 xx 10^-5)= 20.83^@ C` `:.` New temperature `= (30 + 20.83) = 50.83^@ C`

Discussion

52.	The scale on a steel on a steel meter stick is calibrated at `15^@ C`. What is the error in the reading of `60 cm` at `27^@C` ? `alpha_(steel) =1.2 xx 10^-5 (.^@ C)^-1`.
Answer» Correct Answer - C::D The error in the reading will be `Deltal = ("scale reading") (alpha)(Delta T)` `= (60) (1.2 xx 10^-5)(27^@ - 15^@)` = `0.00864 cm`.

Discussion

53.	The coefficient of linear expansion of steel and brass are `11 xx 10^-6//^@ C` and `19 xx 10^-6// ^@ C`, respectively. If their difference in lengths at all temperature has to kept constant at `30 cm`, their lengths at `0^@ C` should beA. `71.25 cm and 41.25 cm`B. `82 cm and 52 cm`C. `92 cm and 62 cm`D. `62.25 cm and 32.25 cm`
Answer» Correct Answer - A `Delta l_1 = Delta l_2` `:. L_(1) alpha_(1) Delta theta = l_(2) alpha_(2) Delta theta` or `(l_1)/(l_2) = (alpha_2)/(alpha_1)= (9)/(11)` In option (a), ratio is `(19)/(11)`.

Discussion

54.	A brass disc fits snugly in a hole in a steel plate. Shou,d you heat or cool tyhe system to losen the disc from the hole ? given that `alpha _b gt alpha _Fe`.
Answer» Correct Answer - C. Since, `alpha_ B gt alpha_(Fe)` On cooling brass will contract more.

Discussion

55.	A steel rod of length `1 m` is heated from `25^@ "to" 75^@ C` keeping its length constant. The longitudinal strain developed in the rod is ( Given, coefficient of linear expansion of steel = `12 xx 10^-6//^@ C`).A. `6 xx 10^-4`B. `-6 xx 10^-5`C. `-6 xx 10^-4`D. zero
Answer» Correct Answer - C It means rod is compressed from its natural length by `Delta l`. `:.` Strain `= - (Delta l)/l = -(l Delta alpha Delta theta)/l` `= (- alpha d theta) = - (12 xx 10^-6)(50)` = `- 6 xx 10^-4`.

Discussion

56.	An ideal thermometer should haveA. Large heat capacityB. Medium heat capacityC. Small heat capacityD. Variable heat capacity
Answer» Correct Answer - c

Discussion

57.	The coefficient of volumetric expansion of mercury is `18xx10^(-5)//^(@)C` . A thermometer bulb has a volume `10^(-6)m^(3)` and cross section of stem is `0.004 cm^(2)`. Assuming that bulb is filled with mercury at `0^(@)C` then the length of the mercury column at `100^(@)C` isA. `18.8 mm`B. `9.2 mm`C. `7.4 mm`D. `4.5 cm`
Answer» Correct Answer - D

Discussion

58.	On a thermometer, the freezing points of water is marked as `20^(@)C` and the boiling points of water is marked as `150^(@)C` . A temperature of `60^(@)C` will be read on this thermometer asA. `98^(@)C`B. `110^(@)C`C. `40^(@)C`D. `60^(@)C`
Answer» Correct Answer - A

Discussion

59.	The freezing point of the liquid decreases when pressure is increased, if the liquidA. Expands while freezingB. Contracts while freezingC. Does not change in volume while freezingD. None of these
Answer» Correct Answer - A

Discussion

60.	A block of mass `100g` slides on a rough horizontal surface, if the speed of the block decreases from `10ms^(-1)` to `5ms^(-1)`, find the thermal energy developed in the process.A. `3.75 J`B. `37.5 J`C. `0.375 J`D. `0.75 J`
Answer» Correct Answer - A

Discussion

61.	Assertion : The melting point of ice decreases with increase of pressure Reason : Ice contract on melting.A. Increases with increasing pressureB. Decreases with increasing pressureC. Is independent of pressureD. Is proportional to pressure
Answer» Correct Answer - B

Discussion

62.	A glass flask of volume one litre at `0^(@)C` is filled, level full of mercury at this temperature. The flask and mercury are now heated to `100^(@)C`. How much mercury will spill out if coefficient of volume expansion of mercury is `1.82 xx 10^(-4)//^(@)C` and linear expansion of glass is `0.1 xx 10^(-4)//^(@)C` respectively?A. `21.2c c`B. `15.2c c`C. `1.52c c`D. `2.12c c`
Answer» Correct Answer - B

Discussion

63.	Assertion : When a solid iron ball is heated, percentage increase is its volume is largest. Reason : Coefficient of superficial expansion is twice that of linear expansion where as coefficient of volume expansion is three time of linear expansion.A. If both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertion.C. If assertion is true but reason is falseD. If the assertion and reason both are false
Answer» Correct Answer - A

Discussion

64.	A metal ball immersed in alcohol weights `W_1` at `0^@C` and `W_2` at `50^@C`. The coefficient of expansion of cubical the metal is less than that of the alcohol. Assuming that the density of the metal is large compared to that of alcohol, it can be shown thatA. `W_(1)gtW_(2)`B. `W_(1)=W_(2)`C. `W_(1)lt W_(2)`D. `W_(2)=(W_(1)//2)`
Answer» Correct Answer - C

Discussion

65.	In supplying 400 calories of heat to a system, the work done will beA. 400 joulesB. 1672 joulesC. 1672 wattsD. 1672 regs
Answer» Correct Answer - B

Discussion

66.	The portion `AB` of the indicator diagram representing the state of matter denots A. The liquid state of matterB. Gaseous state of matterC. Change from liquid to gaseous stateD. Change from gaseous state to liquid state
Answer» Correct Answer - A

Discussion

67.	State whether `(p_1 gt p_2 or p_2 gt p_1)` for given mass of a gas ? .
Answer» Correct Answer - A::B `V = (n R T)/p =((n R)/p) T` For given mass, (V - T) graph is a straight line passing through origin having slope = `(n R)/p prop 1/p` Slope of `(p_2)` is more. Hence, `(p_2 lt p_1)`.

Discussion

68.	A compressor pumps `70 L` of air into a `6 L` tank with the tempertaure remaining unchanged. If all the air is originally at `1 atm`. What is the fianl absolute pressure of the air in the tank ?
Answer» Correct Answer - A::B If (T) = constant, then `p_1 V_1 = p_2 V_2` `:. p_2 = p_1((V_1)/(V_2)) = (1 atm) = (70/6)` = `11.7 atm`.

Discussion

69.	If pressure of an ideal gas is doubled and volume is halved, then its internal energy will remain unchanged. Internal energy of an ideal gas is a function of only temperature.A. If both Assertion and Reason are true and the reason is correct explanation of the Assertion.B. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.C. If Assertion is true, but the Reason is false.D. If Assertion is false but the Reason is true.
Answer» Correct Answer - B `U prop T prop pV`.

Discussion

70.	Fire is extinguished more effectively byA. Hot waterB. Cold waterC. Equally by bothD. Ice
Answer» Correct Answer - a

Discussion

71.	Magnitude of joule’s mechanical equivalent of heat in SI is : (A) 4.2 x 107. (B) 4.2 x 103. (C) 4.2 (D) 1.
Answer» Answer is (D) 1 In SI, both heat and energy are measured in joules and so the joule’s mechanical equivalent of heat, which is a conversion factor is 1.

71.

Magnitude of joule’s mechanical equivalent of heat in SI is : (A) 4.2 x 107. (B) 4.2 x 103. (C) 4.2 (D) 1.

Answer»

Answer is (D) 1

In SI, both heat and energy are measured in joules and so the joule’s mechanical equivalent of heat, which is a conversion factor is 1.

Discussion

72.	Taking the unit of work as joule and the unit of amount of heat as kcal, the magnitude of joule’s mechanical equivalence of heat is : (A) 1 (B) 4.2 (C) 4.2 x 103. (D) 4.2 x 107.
Answer» Answer is (C) 4.2 x 10³. Joule’s mechanical equivalent of heat = work/heat = 4.2H/1cal = 4.2 x 10³ J(kcal^-1)

72.

Taking the unit of work as joule and the unit of amount of heat as kcal, the magnitude of joule’s mechanical equivalence of heat is : (A) 1 (B) 4.2 (C) 4.2 x 103. (D) 4.2 x 107.

Answer»

Answer is (C) 4.2 x 10³.

Joule’s mechanical equivalent of heat = work/heat = 4.2H/1cal

= 4.2 x 10³ J(kcal^-1)

Discussion

73.	Find the mass (in kilogram) of an ammonia molecule `NH_(3)`.
Answer» Correct Answer - A::B Mass of `6.02 xx 10^23 "molecules is" 17 g or 0.017 kg` Mass of one `NH_(3)` molecule =`(0.017)/(6.02 xx 10^23) kg` = `2.82 xx 10^-26 kg`.

Discussion

74.	A vessel contains a mixture of `7 g` of nitrogen and `11 g` carbon dioxide at temperature ` T = 290 K`. If pressure of the mixure is `1 atm (= 1.01 xx 10^5 N//m^2)`, calculate its dencity `(R = 8.31 J//mol - K)`.
Answer» Correct Answer - A::C `(n_1) =` number of moles of nitrogen = `7/(28) = 1/4` `(n_2) =` number of moles of `CO_2 = (11)/(44) = 1/4` `M = (n_1 M_1 + n_2 M_2)/(n_1 + n_2)` = `((1/4)(28)+(1/4)(44))/((1/4)+(1/4))= 36` Now, `rho = (RM)/(RT)` = `((1.01 xx 10^5)(36 xx 10^-3))/((8.31)(290))` = `1.5 kg //m^3`.

Discussion

75.	Assertion: Specific heat of a body is always greater than its thermal capacity. Reason: Thermal capacity is the heat required for raising temperature of unit mass of the body through unit degreeA. If both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertion.C. If assertion is true but reason is falseD. If the assertion and reason both are false
Answer» Correct Answer - D

Discussion

76.	Assertion : The coefficient of volume expansion has dimension `K^(-1)`. Reason : The coefficient of volume expansion is defined as the change in volume per unit volume per unit change in temperature.A. If both assertion and reason are true and the reason is the correct explanation of the assertion.B. If both assertion and reason are true but reason is not the correct explanation of the assertion.C. If assertion is true but reason is falseD. If the assertion and reason both are false
Answer» Correct Answer - A

Discussion

77.	What does Thermal motion mean ? (A) Motion due to heat engine. (B) disorderly motion of the body as a whole. (c) Motion of the body that generates heat. (d) Random motion of molecules.
Answer» Answer is (A) 0.001 kcal Heat required to raise the temperature of 1 gram of water through 1° C is 1 cal = 0.001 kcal.

77.

What does Thermal motion mean ? (A) Motion due to heat engine. (B) disorderly motion of the body as a whole. (c) Motion of the body that generates heat. (d) Random motion of molecules.

Answer»

Answer is (A) 0.001 kcal

Heat required to raise the temperature of 1 gram of water through 1° C is 1 cal = 0.001 kcal.

Discussion

78.	The direction of flow of heat between the two bodies is determined by (A) kinetic energy (B) total energy (C) internal energy(D) none of the above.
Answer» Answer is (D) none of the above.

Discussion

79.	We need mechanical equivalent of heat because :(A) it converts work into heat. (B) in cgs system, heat is not measured in the units of work (C) in SI, heat is measured in the units of work. (D) of some reason other than those mentioned above.
Answer» Answer is (B) in cgs system, heat is not measured in the units of work Mechanical equivalent relates heat in calories to the equivalent amount of work in joules.

79.

We need mechanical equivalent of heat because :(A) it converts work into heat. (B) in cgs system, heat is not measured in the units of work (C) in SI, heat is measured in the units of work. (D) of some reason other than those mentioned above.

Answer»

Answer is (B) in cgs system, heat is not measured in the units of work

Mechanical equivalent relates heat in calories to the equivalent amount of work in joules.

Discussion

80.	‘Stem Correction’ in platinum resistance thermometers are eliminated by the use ofA. CellsB. ElectrodesC. Compensating leadsD. None of the above
Answer» Correct Answer - C

Discussion

81.	Of two masses of 5 kg each falling from height of 10 m , by which 2 kg water is stirred. The rise in temperature of water will beA. `2.6^(@)C`B. `1.2^(@)C`C. `0.32^(@)C`D. `0.12^(@)C`
Answer» Correct Answer - D

Discussion

82.	By exerting a certain amount of pressure on an ice block, youA. Lower its melting pointB. Make it melt at `0^(@)C` onlyC. Make it melt at a faster rateD. Raise its melting point
Answer» Correct Answer - A

Discussion

83.	When we rub our hands they become warm. Have we supplied heat to the hands?A. Heat is absorbed by our palmB. Heat is lost in the environmentC. Produced of heat is stoppedD. None of the above
Answer» Correct Answer - B

Discussion

84.	At NTP water boils at `100^(@)C` . Deep down the mine, water will boil at a temperatureA. Higher temperatureB. Lower temperatureC. At the same temperatureD. At critical temperature
Answer» Correct Answer - B

Discussion

85.	During constant temperature, we feel colder on a day when the relative humidity will beA. `25%`B. `12.5%`C. `50%`D. `75%`
Answer» Correct Answer - A

Discussion

86.	The relative humidity on a day, when partial pressure of water vapour is `0.012xx10^(5)` Pa at `12^(@)C` is (take vapour pressure of water at this temperature as `0.016xx10^(5)` Pa)A. `70%`B. `40%`C. `75%`D. `25%`
Answer» Correct Answer - C

Discussion

87.	A liquid boils when its vapour pressure equalsA. The atmospheric pressureB. Pressure of `76.0 cm` column of mercuryC. The critical pressureD. The dew point of the surroundings
Answer» Correct Answer - A

Discussion

88.	The saturation vapour pressure of water at `100^(@)C` isA. 739 mm of mercuryB. 750 mm of mercuryC. 760 mm of mercuryD. 712 mm of mercury
Answer» Correct Answer - C

Discussion

89.	In the (p - V) diagram shown in figure, choose the correct options for the the process (a - b) : .A. debsity of gas reduced to halfB. temperature of gas has increased to two times.C. internal energy of gas has increased to four timesD. (T - V)graph is a parabola passing thriugh origin
Answer» Correct Answer - A::C::D `rho prop (1)/(V)` (V) is doubled so (rho) will remain half. `U prop T prop p V` According to given graph, `p prop V` `:. U prop T prop p^2 or V^2` (V) is doubled, so (U) and (T) both will become four times. `p prop V` `:. (T)/(V) prop V` (as `p prop (T)/(V))` `:. T prop V^2`, or (T - V) garph is a parabola passing through origin.

Discussion

90.	The p-T graph for the given mass of an ideal gas is shown in figure. What inference can be drawn regarding the change in volume (whether it is constant, increasing or decreasing) ? How to proceed Definitely, it is not constant. Because when volume of the gas is constant `p-T` graph is a straight line passing through origin. The given line does not pass through origin, hence volume is not constant. . `V = (nR)((T)/P)` Now, to see volume of the gas we will have to see whether `(T)/(P)` is increasing or decreasing.
Answer» Correct Answer - A::B From the given graph, we can write the `p - T`equation as `p = aT + b` Now, `T _B gt T_A` :. `b/(T_B)lt b/(T_A) or (P/T)_B lt(P/T)_A` or `(T/P)_B gt(P/T)_A` or ` V_B gt V_A` Thus, as we move from `A` to `B`, volume of the gas is increasimg.

Discussion

91.	If a cylinder of diameter `1.0cm` at `30^(@)C` is to be slid into a hole of diameter `0.9997 cm` in a steel plate at the same temperature, the minimum required rise in the temperature of the plate is: (Coefficient of linear expansion of steel`= 12 xx 10^(-6//@)C`)A. `25^(@)C`B. `35^(@)C`C. `45^(@)C`D. `35^(@)C`
Answer» Correct Answer - A

Discussion

92.	Which of the following curve represent variation of density of water with temperature best-A. B. C. D.
Answer» Correct Answer - A

Discussion

93.	Maximum density of `H_(2)O` is at the temperatureA. `32^(@)F`B. `39.2^(@)F`C. `42^(@)F`D. `4^(@)F`
Answer» Correct Answer - B

Discussion

94.	Thermoelectric thermometer is based onA. Photoelectric effectB. Seeback effectC. Compton effectD. Joule effect
Answer» Correct Answer - B

Discussion

95.	The absolute zero is the temperature at whichA. Matter ceases to existB. Ice melts and water freezesC. Volume and pressure of a gas becomes zeroD. None of these
Answer» Correct Answer - C

Discussion

96.	Expansion during heatingA. Occurs only in solidsB. Increases the weight of a materialC. Decreases the density of a materialD. Occurs at the same rate for all liquids and solids
Answer» Correct Answer - C

Discussion

97.	Two substances A and B of equal mass m are heated at uniform rate of `6 cal s^(-1)` under similar conditions. A graph between temperature and time is shown in figure. Ratio of heat absorbed `H_(A)//H_(B)` by them for complete fusion is A. `(9)/(4)`B. `(4)/(9)`C. `(8)/(5)`D. `(5)/(8)`
Answer» Correct Answer - C

Discussion

98.	When a rod is heated but prevented from expanding, the stress developed is independent ofA. Material of the rodB. Rise in temperatureC. Length of rodD. None of above
Answer» Correct Answer - C

Discussion

99.	A bar of iron is 10 cm at `20^(@)C`. At `19^(@)C` it will be (`alpha` of iron `=11xx10.//^(@)C`)A. `11xx10` cm longerB. `11xx10` cm shorterC. `11xx10` cm shorterD. `11xx10` cm longer
Answer» Correct Answer - C

Discussion

100.	Calorimeters are made of which of the followingA. GlassB. MetalC. WoodD. Either (a) or (c )
Answer» Correct Answer - B

Discussion

Explore topic-wise InterviewSolutions in .

The scale on a steel on a steel meter stick is calibrated at `15^@ C`. What is the error in the reading of `60 cm` at `27^@C` ? `alpha_(steel) =1.2 xx 10^-5 (.^@ C)^-1`.

A brass disc fits snugly in a hole in a steel plate. Shou,d you heat or cool tyhe system to losen the disc from the hole ? given that `alpha _b gt alpha _Fe`.

A steel rod of length `1 m` is heated from `25^@ "to" 75^@ C` keeping its length constant. The longitudinal strain developed in the rod is ( Given, coefficient of linear expansion of steel = `12 xx 10^-6//^@ C`).A. `6 xx 10^-4`B. `-6 xx 10^-5`C. `-6 xx 10^-4`D. zero

An ideal thermometer should haveA. Large heat capacityB. Medium heat capacityC. Small heat capacityD. Variable heat capacity

On a thermometer, the freezing points of water is marked as `20^(@)C` and the boiling points of water is marked as `150^(@)C` . A temperature of `60^(@)C` will be read on this thermometer asA. `98^(@)C`B. `110^(@)C`C. `40^(@)C`D. `60^(@)C`

The freezing point of the liquid decreases when pressure is increased, if the liquidA. Expands while freezingB. Contracts while freezingC. Does not change in volume while freezingD. None of these

A block of mass `100g` slides on a rough horizontal surface, if the speed of the block decreases from `10ms^(-1)` to `5ms^(-1)`, find the thermal energy developed in the process.A. `3.75 J`B. `37.5 J`C. `0.375 J`D. `0.75 J`

Assertion : The melting point of ice decreases with increase of pressure Reason : Ice contract on melting.A. Increases with increasing pressureB. Decreases with increasing pressureC. Is independent of pressureD. Is proportional to pressure

In supplying 400 calories of heat to a system, the work done will beA. 400 joulesB. 1672 joulesC. 1672 wattsD. 1672 regs

The portion `AB` of the indicator diagram representing the state of matter denots A. The liquid state of matterB. Gaseous state of matterC. Change from liquid to gaseous stateD. Change from gaseous state to liquid state

State whether `(p_1 gt p_2 or p_2 gt p_1)` for given mass of a gas ? .

A compressor pumps `70 L` of air into a `6 L` tank with the tempertaure remaining unchanged. If all the air is originally at `1 atm`. What is the fianl absolute pressure of the air in the tank ?

Fire is extinguished more effectively byA. Hot waterB. Cold waterC. Equally by bothD. Ice

Magnitude of joule’s mechanical equivalent of heat in SI is : (A) 4.2 x 107. (B) 4.2 x 103. (C) 4.2 (D) 1.

Taking the unit of work as joule and the unit of amount of heat as kcal, the magnitude of joule’s mechanical equivalence of heat is : (A) 1 (B) 4.2 (C) 4.2 x 103. (D) 4.2 x 107.

Find the mass (in kilogram) of an ammonia molecule `NH_(3)`.

A vessel contains a mixture of `7 g` of nitrogen and `11 g` carbon dioxide at temperature ` T = 290 K`. If pressure of the mixure is `1 atm (= 1.01 xx 10^5 N//m^2)`, calculate its dencity `(R = 8.31 J//mol - K)`.

What does Thermal motion mean ? (A) Motion due to heat engine. (B) disorderly motion of the body as a whole. (c) Motion of the body that generates heat. (d) Random motion of molecules.

The direction of flow of heat between the two bodies is determined by (A) kinetic energy (B) total energy (C) internal energy(D) none of the above.

We need mechanical equivalent of heat because :(A) it converts work into heat. (B) in cgs system, heat is not measured in the units of work (C) in SI, heat is measured in the units of work. (D) of some reason other than those mentioned above.

‘Stem Correction’ in platinum resistance thermometers are eliminated by the use ofA. CellsB. ElectrodesC. Compensating leadsD. None of the above

Of two masses of 5 kg each falling from height of 10 m , by which 2 kg water is stirred. The rise in temperature of water will beA. `2.6^(@)C`B. `1.2^(@)C`C. `0.32^(@)C`D. `0.12^(@)C`

By exerting a certain amount of pressure on an ice block, youA. Lower its melting pointB. Make it melt at `0^(@)C` onlyC. Make it melt at a faster rateD. Raise its melting point

When we rub our hands they become warm. Have we supplied heat to the hands?A. Heat is absorbed by our palmB. Heat is lost in the environmentC. Produced of heat is stoppedD. None of the above

At NTP water boils at `100^(@)C` . Deep down the mine, water will boil at a temperatureA. Higher temperatureB. Lower temperatureC. At the same temperatureD. At critical temperature

During constant temperature, we feel colder on a day when the relative humidity will beA. `25%`B. `12.5%`C. `50%`D. `75%`

The relative humidity on a day, when partial pressure of water vapour is `0.012xx10^(5)` Pa at `12^(@)C` is (take vapour pressure of water at this temperature as `0.016xx10^(5)` Pa)A. `70%`B. `40%`C. `75%`D. `25%`

A liquid boils when its vapour pressure equalsA. The atmospheric pressureB. Pressure of `76.0 cm` column of mercuryC. The critical pressureD. The dew point of the surroundings

The saturation vapour pressure of water at `100^(@)C` isA. 739 mm of mercuryB. 750 mm of mercuryC. 760 mm of mercuryD. 712 mm of mercury

In the (p - V) diagram shown in figure, choose the correct options for the the process (a - b) : .A. debsity of gas reduced to halfB. temperature of gas has increased to two times.C. internal energy of gas has increased to four timesD. (T - V)graph is a parabola passing thriugh origin

Which of the following curve represent variation of density of water with temperature best-A. B. C. D.

Maximum density of `H_(2)O` is at the temperatureA. `32^(@)F`B. `39.2^(@)F`C. `42^(@)F`D. `4^(@)F`

Thermoelectric thermometer is based onA. Photoelectric effectB. Seeback effectC. Compton effectD. Joule effect

The absolute zero is the temperature at whichA. Matter ceases to existB. Ice melts and water freezesC. Volume and pressure of a gas becomes zeroD. None of these

Expansion during heatingA. Occurs only in solidsB. Increases the weight of a materialC. Decreases the density of a materialD. Occurs at the same rate for all liquids and solids

Two substances A and B of equal mass m are heated at uniform rate of `6 cal s^(-1)` under similar conditions. A graph between temperature and time is shown in figure. Ratio of heat absorbed `H_(A)//H_(B)` by them for complete fusion is A. `(9)/(4)`B. `(4)/(9)`C. `(8)/(5)`D. `(5)/(8)`

When a rod is heated but prevented from expanding, the stress developed is independent ofA. Material of the rodB. Rise in temperatureC. Length of rodD. None of above

A bar of iron is 10 cm at `20^(@)C`. At `19^(@)C` it will be (`alpha` of iron `=11xx10.//^(@)C`)A. `11xx10` cm longerB. `11xx10` cm shorterC. `11xx10` cm shorterD. `11xx10` cm longer

Calorimeters are made of which of the followingA. GlassB. MetalC. WoodD. Either (a) or (c )