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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 751. |
1 calorie equals ……… (a) 0.42 J (b) 4.2 J (c) 420 J (d) 4200 J |
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Answer» 1 calorie equals 4.2 J. |
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| 752. |
State the relation between the erg and the joule. |
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Answer» 1 joule = 107 ergs. |
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| 753. |
State the relation between the joule and the calorie. |
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Answer» 1 calorie = 4.18 joules. |
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| 754. |
Write the relation between joule and calorie. |
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Answer» 1 Calorie = 4.186 J. 1 K cal = 4186 J = 4.186 KJ |
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| 755. |
What is the S.I. unit of temperature? |
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Answer» S.l. unit of temperature is Kelvin (K). |
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| 756. |
Give relation between calorie and joule. |
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Answer» 1 cal = 4.18 J |
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| 757. |
Find the heat required to convert 20 g of ice at 0 °C into water at the same temperature. (Specific latent heat of fusion of ice = 80 cal/g) |
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Answer» Answer is 1600 cal |
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| 758. |
How many calories of heat will be absorbed when 3 kg of ice at 0 °C melts? |
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Answer» m = 3 kg = 3000 g; L = 80 cal/g; Q = ? Quantity of heat absorbed, Q = mL = 3000 g × 80 cal/g ∴ Q = 240000 calories. |
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| 759. |
Rewrite the following statements by selecting the correct options:i. Heat absorbed when 1 g of ice melts at 0 °C to form 1 g of water at the same temperature is………..cal.(a) 80(b) 800 (c) 540 (d) 54ii. The latent heat of vaporization of water is……….. (a) 540 cal/g (b) 800 cal/g (c) 80 cal/g (d) 54 cal/giii. The latent heat of fusion of ice is……….. (a) 540 cal/g (b) 80 cal/g (c) 800 cal/g (d) 4cal/giv. If the temperature of water is decreased from 4°C to 10°C, then its……….. (a) volume decreases and density increases (b) volume increases and density decreases (c) volume decreases and density decreases (d) volume increases and density increasesv. At 4°C, the density of water is………..(a) 10 g/cm3(b) 4g/cm3(c) 4 × 103 kg/m3(d) 1 × 103 kg/m3 |
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Answer» i. (a) 80 ii. (a) 540 cal/g iii. (b) 80 cal/g iv. (b) volume increases and density decreases v. (d) 1 × 103 kg/m3 |
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| 760. |
Calculate the amount of heat required to convert 5 g of ice of 0 °C into water at 0 °C. (Specific latent heat of fusion of ice = 80 cal/g) |
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Answer» Here, m = 5 g, L = 80 cal/g; Q = ? Amount of heat required, Q = mL = 5 g × 80 cal/g = 400 calories. |
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| 761. |
The specific latent heat of fusion of ice is 80 cal/g. Explain this statement. |
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Answer» When 1 g of ice at a pressure of one atmospher and at a temperature 0 °C is converted into 1 g of water, heat absorbed by the ice is 80 cal. |
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| 762. |
How many calories of heat will be absorbed when 2 kg of ice at 0 °C melts? (Specific latent heat of fusion of ice = 80 cal/g) |
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Answer» Answer is 160000 cal |
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| 763. |
To keep her soup warm Paheli wrapped the container in which it was kept with a woollen cloth. Can she apply the same method to keep a glass of cold drink cool? Give reason for your answer. |
| Answer» Yes. Wool is poor conductor of heat. | |
| 764. |
Calculate the heat required to convert 3 kg of ice at `-12^(@)C` kept in a calorimeter to steam at `100^(@)C` at atmospheric pressure. Given, specific heat capacity of ice = `2100 J kg^(-1) K^(-1)` specific heat capicity of water = `4186 J kg^(-1)K^(-1)` Latent heat of fusion of ice = ` 3.35 xx 10^(5) J kg^(-1)` and latent heat of steam = ` 2.256 xx 10^(6) J kg^(-1)` . |
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Answer» Correct Answer - `3.045 xx 10^(6)J` |
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| 765. |
A copper calorimeter of mass 100 g contians 200 g of ice at `-10^(@)C`. The thermal energy is upplied to the calorimeter and its contents at the rate of 50 calories per second. What is temperature of the calorimeter and its contents after ten minutes. (Given, the specific heat of ice `=0.5 cal g^(-1)""^(@)C^(-1)`, the specific heat of copper `=0.1 cal g^(-1)""^(@)C^(-1)`, and latent heat of fusion of ice `=80 cal g^(-1)` |
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Answer» (i) Use `=mL and Q= ms Delta theta ` according to the situation. Use principle of calorimetery. Total heat produced = (mass of the substance ) `xx` (calorific value of the substance). (ii) `5.46 MJ kg^(-1)` |
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| 766. |
What is the heat in joules required to raise the temperature of 25 grams of water from 0°C to 100°C? What is the heat in Calories? (Specific heat of water = 4.18 J/g°C). |
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Answer» Given m = 25 g, ∆T = (100 – 0) = 100°C Or in terms of Kelvin (373.15 – 273.15) = 100K, C = 4.18J/g°C Heat energy required, Q = m × C × ∆T = 25 × 4.18 × 100 = 10450 J |
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| 767. |
A copper calorimeter of mass 100 g and temperature 30 °C contains water of mass 200 g and temperature 30 °C. If a piece of ice of mass 40 g and temperature 0 °C is added to it, what will be the maximum temperature of the mixture? [c (copper) = 0.1 cal/g·°C, c (water) = 1 cal/g·°C, L = 80 cal/g] |
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Answer» Answer is 12.4 °C |
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| 768. |
The heat energy required to raise the temperature of 20 kg of water from 25 °C to 75 °C is (in calories) ………………… A) 103 B) 104 C) 105 D) 106 |
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Answer» Correct option is D) 106 |
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| 769. |
Water of mass 200 g and temperature 30 °C is taken in a copper calorimeter of mass 50 g and temperature 30 °C. A copper sphere of mass 100 g and temperature 100 °C is released into it. What will be the maximum temperature of the mixture? [c (water) = 1 cal/g·°C, c (copper) =0.1 cal/g·°C] |
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Answer» Answer is 33.26 °C |
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| 770. |
If water of mass 60 g and temperature 60 °C is mixed with water of mass 60 g and temperature 40 °C, what will be the maximum temperature of the mixture? |
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Answer» Answer is 50 °C |
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| 771. |
Find the heat needed to raise the temperature of a piece of iron of mass 500 g by 20 °C. (c = 0.110 cal/g·°C) |
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Answer» Answer is 1100 cal |
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| 772. |
Fill in the blanks :(a) No medium is required for transfer of heat by the process of .......... (b) A cold steel spoon is dipped in a cup of hot milk. It transfers heat to its other end by the process of ...........(c) Clothes of ........colours absorb heat better than clothes of light colours. |
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Answer» (a) No medium is required for transfer of heat by the process of Radiation. (b) A cold steel spoon is dipped in a cup of hot milk. It transfers heat to its other end by the process of Conduction. (c) Clothes of Dark colours absorb heat better than clothes of light colours. |
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| 773. |
Match the following :(i) Land breeze blows during(a) Summer(ii) Sea breeze blows during(b) Winter(iii) Dark coloured clothes are preferred during(c) day(iv) Light coloured clothes are preferred during(d) Night |
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Answer» i – d, ii – c, iii – b, iv – a |
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| 774. |
Discuss why wearing more layers of clothing during winter keeps us warmer than wearing just one thick piece of clothing. |
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Answer» More layers of clothing keep us warm in winters as they have a lot of space between them. This space gets filled up with air. Air is a bad conductor, it does not allow the body heat to escape out. |
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| 775. |
Which of the following expands on heating and contracts on cooling? A) Solid B) Liquid C) GasD) All |
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Answer» The correct option is D) All. |
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| 776. |
Ventilators are working on A) Air expands on heating B) Air contracts on heating C) Metal expands on heating D) Air contracts on cooling |
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Answer» The correct option is A) Air expands on heating. |
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| 777. |
Why does the mercury level of thermometer rise up when it is placed in hot water and fall down when it is placed in cold water? |
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Answer» 1. We know that bodies which are in contact achieve thermal equilibrium due to transfer of heat energy. 2. If we keep thermometer in hot water, its mercury level rises because heat is transformed from hot body to cold body. 3. Similarly, we observe that mercury level comes down when it is placed in cold water. |
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| 778. |
From the given figure, in which the thermometer mercury level is increases and decreases? |
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Answer» Thermometer A(in oil) is increases. Thermometer B(water) is decreases. |
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| 779. |
When we place thermometer in hot water, there is a rise in mercury level, thereafter it stops. What is the reason for steadiness of mercury level? What does reading of thermometer give at that time? |
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Answer» 1. The steadiness of the mercury column of the thermometer indicates that, flow of heat between the thermometer liquid (mercury) and water has stopped and thermal equilibrium has been attained between the water and thermometer liquid. 2. The reading of thermometer gives thermal equilibrium state that is temperature. |
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| 780. |
Which of the following thermometer scale is also known as absolute scale of temperature? A) Celsius scale B) Fahrenheit scale C) Kelvin scale D) None |
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Answer» C) Kelvin scale |
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| 781. |
The temperature of a steel rod is 330 K. Its temperature in °C is …………………….. A) 55° C B) 59° C C) 53° C D) 57° C |
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Answer» Correct option is D) 57° C |
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| 782. |
The boiling point of liquid depneds onA. its nature.B. super incumbent pressure.C. its purityD. All the above |
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Answer» Correct Answer - D Boiling point of a liquid depends on its nature, super incumbent pressure, and also on the level of impurities present in it. |
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| 783. |
The amount of heat energy absorbed by the substance to change completely form liquid at its boiling point to gaseous state is ______J A. 4618B. 2270C. 4538D. 4958 |
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Answer» Correct Answer - b The substacne in liquid stae changes to gaseous state by absorbing energy of 2690-420 =2270 J |
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| 784. |
Define boiling point of a liquid.(OR)What is boiling point of a liquid? |
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Answer» The constant temperature at which a liquid transforms into gaseous state is called the boiling point of the liquid. [Note: On application of pressure, the boiling point of a liquid is raised. On reducting the pressure, the boiling point is lowered.] |
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| 785. |
Choose the correct statement: (a) During boiling a liquid change in to gaseous state at constant temperaute with absorption of heat energy (b) During solidification a liquid changes in to solid state at constant temperature with release of heat energyA. only aB. only bC. both a and bD. none of these |
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Answer» Correct Answer - c Both the given statement are true |
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| 786. |
Boiling point. |
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Answer» Boiling point: The temperature at which liquid undergoes boiling. |
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| 787. |
The latent heat of fusion of a solid ‘ substance of mass “m” is L. The required amount of heat to change solid phase to liquid phase is ……………… cal. A) Q = mL B) Q = mSΔt C) 80 D) 540 |
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Answer» Correct option is A) Q = mL |
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| 788. |
Define boiling point of liquid. |
| Answer» The constant temperature at which a liquid transforms into gaseous state, is called boiling point of that substance. | |
| 789. |
Define latent heat of Fusion. |
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Answer» Latent heat of Fusion : At constant temperature, the heat energy required to convert one gram of solid completely into liquid is called latent heat of Fusion. |
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| 790. |
What is Latent heat of fusion ? |
| Answer» The amount of heat energy absorbed at constant temperature during transformation of solid into liquid is called latent heat of fusion. | |
| 791. |
Why do we use white clothes in summer and dark or black clothes in winter? |
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Answer» 1. White clothes do not absorb heat, so in summer, weather is very hot and white clothes protect us from heat whereas in winter it is very cold so we need more heat. 2. Dark or black clothes absorb more heat so we get protection from cold. |
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| 792. |
Why do we prefer to wear white or light coloured clothes in summer and black or dark coloured clothes in winter ? |
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Answer» We prefer to wear white clothes in summer. The reason is that the white clothes reflects most of the sun’s heat and absorb very little of the sun’s heat, thus they keep our body cool. We prefer to wear black and dark coloured clothes in winter. The reason is that the black or dark colour clothes absorb most of the sun’s heat and keep our body warm. |
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| 793. |
Assertion (A): Black coloured clothes are preferred over white colored clothes in winter Reason (R ): Black is good absorber of radiationA. both a and r are ture and r is the correct explanation of aB. both a and r are true but r is not the correct explanation of aC. a is true but r is falseD. both a and r are false |
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Answer» Correct Answer - d Black coloured clothes are not preferred in summer as black is good absrober of radiation |
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| 794. |
Temperatures of two cities at different times are given as follows:Time→A 6 AMAt 11.30 AMAt 6 PMCityA-3°C300 K5°CB271 K27°C270 KOn the basis of above table, answer the following questions. 1) In which city, the morning temperature at 6 O’clock is relatively high?2) At what time, both cities are having the equal temperature? |
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Answer» 1) In ‘B’ city, the morning temperature at 6 O’clock is relatively high. 2) At 11 : 30 AM, both cities are having the equal temperature. |
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| 795. |
Look at Fig. Mark where the heat is being transferred by conduction, by convection and by radiation. |
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Answer» 1. Transfer of heat from hot plate to pan is by conduction 2. Transfer of heat within water is by convection. 3. Transfer of heat from hot bodies like pan, plate, burner etc. to the surroundings is radiation. |
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| 796. |
Heat in a liquid is transferred by 1. conduction 2. convection 3. radiation 4. conduction and radiation |
| Answer» 2. convection | |
| 797. |
Take hot water in a cup and put a silver spoon in it. Leave the spoon inside the water for some time. Now touch the end of the spoon. Do you feel the heat? |
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Answer» 1. Yes, we feel hot. 2. It is because heat in the hot water is transferred from one end to other end of the spoon. 3. In solid substances such as silver spoon, atoms are arranged very closely. 4. So heat transfer takes place from the higher temperature region to lower temperature region. 5. This is due to conduction. |
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| 798. |
Statement I : During evaporation the temperature of the evaporating liquid decreases. Statement II: During condensation the temperature of the surrounding air increases A) Both I and II are true B) I is true, II is false C) I is false, II is true D) Both I and II are false |
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Answer» A) Both I and II are true |
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| 799. |
Fill in the blanks and rewrite the sentences:i. The amount of water vapour in air is determined in terms of its…………..ii. If objects of equal masses are given equal heat, their final temperature will be different. This is due to difference in their……………iii. When a liquid is getting converted into solid, the latent heat is…………. |
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Answer» i. The amount of water vapour in air is determined in terms of its absolute humidity. ii. If objects of equal masses are given equal heat, their final temperature will be different. This is due to difference in their specific heat capacities. iii. When a liquid is getting converted into solid, the latent heat is released. |
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| 800. |
Rate of evaporation of a liquid depends on ………………….A) surface area B) temperature C) humidity D) all |
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Answer» Correct option is D) all allanswer d is right
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