Science and Technology I · Textbook solutions
Heat
Every solved example, exercise, and miscellaneous question, in the order the textbook teaches them. Plus every board question asked from this chapter. · 22 questions
Exercise
22 q
- Fill in the blanks and rewrite the sentence.Ex Q1(a)The amount of water vapour in air is determined in terms of its …………
- Ex Q1(b)If objects of equal masses are given equal heat, their final temperature will be different. This is due to difference in their ……………...
- Ex Q1(c)During transformation of liquid phase to solid phase, the latent heat is …………..
- Ex Q2Observe the following graph. Considering the change in volume of water as its temperature is raised from , discuss the difference in the behaviour of water and other substances. What is this behaviour of water called?
- Ex Q3What is meant by specific heat capacity? How will you prove experimentally that different substances have different specific heat capacities?
- Ex Q4While deciding the unit for heat, which temperatures interval is chosen? Why?
- Ex Q5Explain the following temperature versus time graph.
- Explain the following:Ex Q6(a)What is the role of anomalous behaviour of water in preserving aquatic life in regions of cold climate?
- Ex Q6(b)How can you relate the formation of water droplets on the outer surface of a bottle taken out of refrigerator with formation of dew?
- Ex Q6(c)In cold regions in winter, the rocks crack due to anomalous expansion of water.
- Answer the following:Ex Q7(a)What is meant by latent heat? How will the state of matter transform if latent heat is given off?
- Ex Q7(b)Which principle is used to measure the specific heat capacity of a substance?
- Ex Q7(c)Explain the role of latent heat in the change of state of a substances?
- Ex Q7(d)On what basis and how will you determine whether air is saturated with vapour or not?
- Read the following paragraph and answer the questions. If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both the objects attain the same value. In this process, the cold object gains heat energy and the hot object loses heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat resistant box (meaning that the energy exchange takes place between the two objects only), then no energy can flow from inside the box or come into the box.Ex Q8(i)Heat is transferred from where to where?
- Ex Q8(ii)Which principle do we learn about from this process?
- Ex Q8(iii)How will you state the principle briefly?
- Ex Q8(iv)Which property of the substance is measured using this principle?
- Solve the following problems:Ex Q9(a)Equal heat is given to two objects A and B of mass 1 g. Temperature of A increases by and B by . Which object has more specific heat? And by what factor?
- Ex Q9(b)Liquid ammonia is used in ice factory for making ice from water. If water at is to be converted into 2 kg ice at , how many grams of ammonia are to be evaporated? (Given: The latent heat of vaporization of ammonia = 341 cal/g)
- Ex Q9(c)A thermally insulated pot has 150 g ice at temperature . How much steam of has to be mixed to it, so that water of temperature will be obtained? (Given : latent heat of melting of ice = 80 cal/g, latent heat of vaporization of water = 540 cal/g, specific heat of water = )
- Ex Q9(d)A calorimeter has mass 100 g and specific heat . It contains 250 gm of liquid at having specific heat of . If we drop a piece of ice of mass 10 g at , What will be the temperature of the mixture?
What the board has asked from this chapter
Questions per paper · 11 papers · 2018 to 2026
2018: 1 questions per paper. 2019: 2 questions per paper. 2020: 3 questions per paper. 2022: 4 questions per paper. 2023: 4 questions per paper. 2024: 2.5 questions per paper. 2025: 2 questions per paper. 2026: 2.5 questions per paper
June 2026
2 q
- Q2(B)(i)खालील आकृतीस नावे देवून या उपकरणाच्या साहाय्याने कोणत्या गुणधर्माचा अभ्यास करता येतो ?Label the following diagram and name the property can be studied using it.Anomalous Behaviour of Water
- Q3(iv)(अ) पुनर्हिमायन म्हणजे काय ? (ब) दाबामुळे बर्फाच्या द्रवणांकावर काय परिणाम होतो ? (क) पुनर्हिमायनाचे एक उदाहरण लिहा.(a) What is meant by Regelation? (b) What is the effect of pressure on melting point of ice? (c) Write any one example of regelation.Latent Heat and Change of State
March 2026
3 q
- Q1(B)(iii)खालील विधान चूक की बरोबर ते सांगा : पाण्याचे आकारमान ला सर्वात जास्त असते.State whether the following statement is true or false: 'The volume of water at C is maximum'.Anomalous Behaviour of Water
- Q1(B)(iv)जोड्या जुळवा :
‘अ’ गट ‘ब’ गट थर्मामीटर (अ) यांत्रिक ऊर्जा (ब) तापमान मोजणे (क) विद्युतधारा मोजणे Match the pairs:Group 'A' Group 'B' Thermometer (a) Mechanical energy (b) To measure temperature (c) To measure electric current Concept of Heat and Temperature - Q3(iii)खालील उताऱ्याचे वाचन करा व विचारलेल्या प्रश्नांची उत्तरे लिहा : उष्ण व थंड वस्तूंमध्ये उष्णतेची देवाणघेवाण झाल्यास उष्ण वस्तूचे तापमान कमी होत जाते व थंड वस्तूचे तापमान वाढत जाते. जोपर्यंत दोन्ही वस्तूंचे तापमान सारखे होत नाही तोपर्यंत तापमानातील हा बदल होत राहतो. या क्रियेत गरम वस्तू उष्णता गमावतो तर थंड वस्तू उष्णता ग्रहण करते. दोन्ही वस्तू फक्त एकमेकांमध्ये ऊर्जेची देवाणघेवाण करू शकतात. अशा स्थितीत असल्यास म्हणजेच जर दोनही वस्तूंची प्रणाली वातावरणापासून वेगळी केल्यास प्रणालीमधून उष्णता आतही येणार नाही किंवा बाहेरही जाणार नाही. (अ) उष्णता स्थानांतरण कोठून कोठे होते ? (ब) अशा स्थितीत आपणास उष्णतेच्या कोणत्या तत्त्वाचा बोध होतो ? (क) ते तत्त्व थोडक्यात कसे सांगता येईल ?Read the following paragraph and answer the questions: If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both the objects attain the same value. In the process, the cold object gains heat energy and the hot object loses heat energy. If the system of both objects is isolated from environment by keeping it inside a heat resistant box, then no energy can flow from inside the box or come into the box. (a) Heat is transferred from where to where? (b) Which principle do we learn from this process? (c) How will you state the principle briefly?Principle of Heat Exchange
July 2025
2 q
- Q2(B)(iv)विशिष्ट उष्माधारकतेची व्याख्या लिहून त्याचे SI एकक व CGS एकक लिहा.Define specific heat of an object. Write its SI and CGS units.Specific Heat Capacity
- Q3(v)वस्तुमान असलेल्या पाण्याचे तापमान पासून पर्यंत वाढविण्यासाठी किती उष्णता लागेल ?How much heat energy is necessary to raise the temperature of 5 kg of water from to ? [ kcal/kg]Specific Heat Capacity
March 2025
2 q
- Q1(B)(v)ते या तापमानादरम्यान असणाऱ्या पाण्याच्या आचरणास काय म्हणतात ?Name the behaviour of water between its temperature from to .Anomalous Behaviour of Water
- Q2(B)(i)पदार्थाच्या विशिष्ट उष्माधारकतेच्या मापनासाठी कोणत्या तत्त्वाचा वापर करतात ? ते तत्त्व लिहा.Name and state the principle used to measure the specific heat capacity of a substance.Specific Heat Capacity
July 2024
2 q
- Q2(B)(ii)आकृतीचे निरीक्षण करून खालील प्रश्नांची उत्तरे लिहा : (अ) आकृतीत दाखविलेल्या प्रक्रियेचे नाव लिहा. (ब) त्या प्रक्रियेची व्याख्या लिहा.Observe the figure and answer the questions given below. (a) Name the phenomenon shown in the figure. (b) Define the above phenomenon.Latent Heat and Change of State
- Q3(viii)(a) पाण्याचे असंगत आचरण म्हणजे काय ? (b) थंड प्रदेशात जलीय वनस्पती व जलचर यांना जिवंत ठेवण्यात पाण्याच्या असंगत आचरणाची भूमिका स्पष्ट करा.(a) What is meant by anomalous behaviour of water? (b) Explain the role of anomalous behaviour of water in preserving aquatic life in cold climate.Anomalous Behaviour of Water
March 2024
3 q
- Q1(A)(i)उष्णतेचे SI पद्धतीतील एकक ____ हे आहे.The SI unit of heat is ______.
Tap an option to check your answer.
Concept of Heat and its Units - Q1(B)(iii)कॅलरीमापीचा उपयोग लिहा.Write the use of 'Calorimeter'.Specific Heat Capacity
- Q3(iii)खालील आलेखाचे निरीक्षण करा आणि विचारलेल्या प्रश्नांची उत्तरे लिहा : (a) दिलेला आलेख काय दर्शवतो ? (b) रेषा AB काय दर्शवते ? (c) रेषा BC काय दर्शवते ?Observe the following graph (temperature vs time on heating ice) and answer the following questions: (a) What does the graph represent? (b) What does the line AB represent? (c) What does the line BC represent?Latent Heat and Change of State
March 2023
4 q
- Q2(B)(i)How do we feel about air in each of the following conditions? (a) Relative humidity is more than 60%. (b) Relative humidity is less than 60%.Humidity and Relative Humidity
- Observe the figure titled 'Specific heat capacity of metals' (identical balls of iron, copper and lead, heated to the same temperature, placed on a layer of wax) and answer the following:Q3(vi)(a)Which element has maximum specific heat capacity? Justify.Specific Heat Capacity
- Q3(vi)(b)Which element has minimum specific heat capacity? Justify.Specific Heat Capacity
- Q3(vi)(c)Define specific heat of an object.Specific Heat Capacity
March 2022
4 q
- Q2(B)(ii)Draw a neat labelled diagram of Hope's Apparatus.Anomalous Behaviour of Water
- Read the following paragraph and answer the questions based on it: If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both the objects attain the same value. In this process, the cold object gains heat energy and the hot object loses heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat resistant box, then no energy can flow from inside the box or come into the box.Q3(v)(a)Heat is transferred from where to where?Principle of Heat Exchange
- Q3(v)(b)Which principle do we learn about from this process?Principle of Heat Exchange
- Q3(v)(c)How will you state the principle briefly?Principle of Heat Exchange
March 2020
3 q
- Q1(A)(ii)The vapour content in the air is measured using a physical quantity called _______.
Tap an option to check your answer.
Humidity - Q2(B)(i)How much heat energy is necessary to raise the temperature of 5 kg of water from to ? (specific heat of water )Specific Heat - Heat Energy Calculation
- Q2(B)(iii)Observe the given graph of the volume of 1 kg of water versus temperature and answer: a. Name the process represented in the figure. b. At what temperature does this process take place?Anomalous Expansion of Water
March 2019
2 q
- Q1(B)(4)Water expands on reducing its temperature below ________ .
Tap an option to check your answer.
Anomalous Behaviour of Water - Q3(4)Explain the given temperature vs time graph (with points A, B, C, D) showing the changes occurring when a mixture of ice and water is heated.Latent Heat and Change of State
March 2018
1 q
- Q1(A)(a)(i)Fill in the blank with a suitable word: 1 calorie = ______ joule.Specific Heat Capacity
The 10 board questions to practise first
The questions the board asked again come first, most asked first. Each one says how often and when.
Question 1
Asked 2 times: Mar 2022, Mar 2026
Q3(iii)खालील उताऱ्याचे वाचन करा व विचारलेल्या प्रश्नांची उत्तरे लिहा : उष्ण व थंड वस्तूंमध्ये उष्णतेची देवाणघेवाण झाल्यास उष्ण वस्तूचे तापमान कमी होत जाते व थंड वस्तूचे तापमान वाढत जाते. जोपर्यंत दोन्ही वस्तूंचे तापमान सारखे होत नाही तोपर्यंत तापमानातील हा बदल होत राहतो. या क्रियेत गरम वस्तू उष्णता गमावतो तर थंड वस्तू उष्णता ग्रहण करते. दोन्ही वस्तू फक्त एकमेकांमध्ये ऊर्जेची देवाणघेवाण करू शकतात. अशा स्थितीत असल्यास म्हणजेच जर दोनही वस्तूंची प्रणाली वातावरणापासून वेगळी केल्यास प्रणालीमधून उष्णता आतही येणार नाही किंवा बाहेरही जाणार नाही. (अ) उष्णता स्थानांतरण कोठून कोठे होते ? (ब) अशा स्थितीत आपणास उष्णतेच्या कोणत्या तत्त्वाचा बोध होतो ? (क) ते तत्त्व थोडक्यात कसे सांगता येईल ?Read the following paragraph and answer the questions: If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both the objects attain the same value. In the process, the cold object gains heat energy and the hot object loses heat energy. If the system of both objects is isolated from environment by keeping it inside a heat resistant box, then no energy can flow from inside the box or come into the box. (a) Heat is transferred from where to where? (b) Which principle do we learn from this process? (c) How will you state the principle briefly?Question 2
Asked 2 times: Mar 2020, Jul 2025* (* = numbers or wording changed that year)
Q3(v)वस्तुमान असलेल्या पाण्याचे तापमान पासून पर्यंत वाढविण्यासाठी किती उष्णता लागेल ?How much heat energy is necessary to raise the temperature of 5 kg of water from to ? [ kcal/kg]Question 3
Asked 2 times: Mar 2019, Mar 2024* (* = numbers or wording changed that year)
Q3(iii)खालील आलेखाचे निरीक्षण करा आणि विचारलेल्या प्रश्नांची उत्तरे लिहा : (a) दिलेला आलेख काय दर्शवतो ? (b) रेषा AB काय दर्शवते ? (c) रेषा BC काय दर्शवते ?Observe the following graph (temperature vs time on heating ice) and answer the following questions: (a) What does the graph represent? (b) What does the line AB represent? (c) What does the line BC represent?Question 4
This type asked 7 times: Mar 2019, Mar 2020, Mar 2022, Jul 2024, Mar 2025, Mar 2026, Jun 2026. This one: Jun 2026
Q2(B)(i)खालील आकृतीस नावे देवून या उपकरणाच्या साहाय्याने कोणत्या गुणधर्माचा अभ्यास करता येतो ?Label the following diagram and name the property can be studied using it.Question 5
This type asked 5 times: Mar 2018, Mar 2023, Mar 2024, Mar 2025, Jul 2025. This one: Jul 2025
Q2(B)(iv)विशिष्ट उष्माधारकतेची व्याख्या लिहून त्याचे SI एकक व CGS एकक लिहा.Define specific heat of an object. Write its SI and CGS units.Question 6
This type asked 3 times: Mar 2019, Jul 2024, Jun 2026. This one: Jun 2026
Q3(iv)(अ) पुनर्हिमायन म्हणजे काय ? (ब) दाबामुळे बर्फाच्या द्रवणांकावर काय परिणाम होतो ? (क) पुनर्हिमायनाचे एक उदाहरण लिहा.(a) What is meant by Regelation? (b) What is the effect of pressure on melting point of ice? (c) Write any one example of regelation.Question 7
This type asked 2 times: Mar 2020, Mar 2023. This one: Mar 2023
Q2(B)(i)How do we feel about air in each of the following conditions? (a) Relative humidity is more than 60%. (b) Relative humidity is less than 60%.Question 8
Asked once: Mar 2026 (same type asked 7 times)
Q1(B)(iii)खालील विधान चूक की बरोबर ते सांगा : पाण्याचे आकारमान ला सर्वात जास्त असते.State whether the following statement is true or false: 'The volume of water at C is maximum'.Question 9
Asked once: Mar 2025 (same type asked 5 times)
Q2(B)(i)पदार्थाच्या विशिष्ट उष्माधारकतेच्या मापनासाठी कोणत्या तत्त्वाचा वापर करतात ? ते तत्त्व लिहा.Name and state the principle used to measure the specific heat capacity of a substance.Question 10
Asked once: Jul 2024 (same type asked 3 times)
Q2(B)(ii)आकृतीचे निरीक्षण करून खालील प्रश्नांची उत्तरे लिहा : (अ) आकृतीत दाखविलेल्या प्रक्रियेचे नाव लिहा. (ब) त्या प्रक्रियेची व्याख्या लिहा.Observe the figure and answer the questions given below. (a) Name the phenomenon shown in the figure. (b) Define the above phenomenon.