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Question: 1
What is meant by thermal expansion?
Answer: 1
1-116If change in temperature cause the change in length, or volume of a substance then it is called as thermal expansion of that substance.
Question: 2
Define coefficient of linear thermal expansion.
Answer: 2
2-116Coefficient of linear thermal expansion can be defined as fraction increase in length per kelvin rise in temperature.
Unit; Its unit is K-1
Question: 3
What is temperature?
Answer: 3
3-116Temperature of a body is the degree of hotness or coldness of body. It change withe the flow of heat.
Unit: Its SI unitis kelvin.
Question: 4
What is meant by internal energy of a body?
Answer: 4
4-116The sum of potential energy and kinetic energy associated with atoms, molecules and particles of a body is called its internal energy.
Question: 5
Define latent heat of fusion.
Answer: 5
5-116Heat energy required to change unit mass of a substance from solid to liquid state at its melting point without change in its temperature is called its latent heat of fusion.
Question: 6
What is thermometer?
Answer: 6
6-116A device which is used to measure the temperature of a body is called thermometer.
Question: 7
What is Kelvin scale of temperature.
Answer: 7
7-116In kelvin scale, the interval between lower and upper fixed points is divided into 100 equal parts.
i. Lower fixed point = 273 oK
ii. Upper fixed point = 373 oK
Question: 8
Define heat capacity of a body.
Answer: 8
8-116Heat capacity of a body is amount of thermal energy absorbed by it for one kelvin rise in temperature.
Heat capacity = mc
Unit: Its unit is JK-1
Question: 9
What is the volumetric thermal expansion.
Answer: 9
9-116The volume of solid changes with the change in temperature and is called volume thermal expansion or cubic thermal expansion.
Question: 10
What is meant by linear thermal expansion.
Answer: 10
10-116If length of solid changes with change in temperature is called linear thermal expansion.
Question: 11
Give two uses of cooling affect by evaporation.
Answer: 11
11-116Evaporation of perspiration helps to cool our bodies
Cooling is produced in refrigerators by evaporation of liquefied gas.
Question: 12
How does heating affect the motion of molecules of a gas
Answer: 12
12-116When a gas is heated, the velocityh of the gas molecules increased due to this reason the motionn of molecules of molecules increased which increases the kinetic energy internal energy and temperature of a gas molecules.
Question: 13
Write a note on centigrade scale.
Answer: 13
13-116On centigrade scale the interval between lower and upper fixed points is divided into 100 equal parts.
i. Lower fixed point is 0 oC
ii. Upper fiexed points is 100 oC
Question: 14
Define specific heat capacity.
Answer: 14
14-116Specific heat capacity of a substance is define as the amount of heat required to raise temperature of one kg mass of that substances through 1 K
Question: 15
What meant by evaporation?
Answer: 15
15-116Evaporation is a changing of a liquid in to vapours from surface of liquid without heating .
Question: 16
What is meant by fusion point
Answer: 16
16-116The temperature at which solid starts melting is called fusion point
Question: 17
What is meant by fusion point?
Answer: 17
17-116The temperature at which solid starts melting is called function point
Example : The Fusion point of ice is 0 oC
Question: 18
Define heat
Answer: 18
18-116Heat is the energy that is transferred from one body to the other in thermal contact with each other as a result of the difference of temperature between them
Question: 19
Which flower is used as natrual thermometer?
Answer: 19
19-116The crocus flower is a natural thermometer. It opens when temperature is precisely 23 oC and closes when temperature drops.
Question: 20
Define upper and lower fixed points of a thermometer.
Answer: 20
20-116Upper fixed point is marked to shw position of liquid in thermometer when it is placed in steam at standard pressure above boiling water.
Question: 21
How does heating, affect the motioin of molecules of a gas
Answer: 21
21-116By heating a gas the molecules vibrate here and there berry fast speed and decreasing the amount of heat the speed reduce.
Question: 22
Why does heat flow from hot body to cold body
Answer: 22
22-116Heat flows from hot body to cold body due to difference of temperature between them . The temperature of hot body decreases because it loses heat. Cold body gains this heat and its temperature increases. The transfer of heat energy continues till both the bodies have same temperature.
Question: 23
What is a relationship between the coefficient of linear and volume expansion.
Answer: 23
23-116The coefficient of linear and volume expansion are related by the equation. Beta = 3a
Question: 24
What is thermometer
Answer: 24
24-116A device which is used to measure the temperature of a body is called thermometer
Question: 25
What are the factors on which internal energy depends upon.
Answer: 25
25-116i. Mass of body
ii. Kinetic energy of a body
iii Potential energy of a body.
Question: 26
How many intervals are in Fahrenheit scale
Answer: 26
26-116In Fahrenheit scale the interval between lower and upper fixed points is divided into 100 equal parts
Lower fixed point =32, Upper fixed point = 212
Question: 27
Why gaps are left in railway tracks.
Answer: 27
27-116Gaps are left in railway tracks to compensate thermal expansion during hot season. Because in summer railway tracks expand due to increase inteeperature.
Question: 28
What is the volumetric thermal expansion
Answer: 28
28-116The volume of solid changes with the change in temperature and is called volume thermal expansion or cubic thermal expansion
Question: 29
Define latent heat of vaporization?
Answer: 29
29-116The quantity of heat the changes unit mass of a liquid completely into gas at its boiling point without any change in its temperature is called latent heat of vaporization.
Question: 30
What is meant by evaporation
Answer: 30
30-116Evaporation is a changing of aa liquid into apours from surface of liquid without heating
Question: 31
What is Fahrenheit temperature scale?
Answer: 31
31-116In fahrenheit scale the interval between lowere and upper fixed points is divided into 180 equal parts.
i. Lower fixed point=32 oC ii. Upper fixed point = 212 oF
Question: 32
Define upper and lower fixed points of a thermometer
Answer: 32
32-116Upper fixed Point: Upper fixed point is marked toi show position of liquid in thermometer when it is placed in steam at standard pressure above boiling water.
Question: 33
Write formula for heat capacity.
Answer: 33
33-116Formula for heat capacity is.
Heat capacity = mc
Question: 34
Write the properties of thermometric substance
Answer: 34
34-116Thermometric substance should be visible have low freezing point high melting point good conductor of heat and small specific heat capacity
Question: 35
Define Lower fixed point.
Answer: 35
35-116Lower fixed point is marked to show position of liquid in thermometer when it is placed in ice.
Question: 36
Define specific heat capacity How would you find the specific heat of a solid
Answer: 36
36-116Specific heat capacity of a substance is defined as the amount of heat required to raise temperature of one kg mass of that substance through
Question: 37
What is meant by freezing point
Answer: 37
37-116The temperature at which a substance changes from liquid to solid state is called its freezing point
Question: 38
What will be heat capacity of 5kg water
Answer: 38
38-116Heat capacity of 1kg water is 4200jkg
Heat capacity of 5kg water 5=5*4200
21000jkg
Question: 39
What is temperature
Answer: 39
39-116Temperature of a body is the degree of hotness or coldness of body It change with the flow of heat
Question: 40
Write formula for heat capacity
Answer: 40
40-116Formula for heat capacity is
Heat capacity = mc
Question: 41
Why temperature of lnd near water remains moderate
Answer: 41
41-116The presence of large water reservoirs such as lakes and seas keep the climate moderate due to large heat capacity of their reservoirs.
Question: 42
Define thermal expansion
Answer: 42
42-116Thermal expansion: Expansion due to heating is called thermal expension
Question: 43
Define latent heat of fusion
Answer: 43
43-116Heat energy required to change unit mass of a substance from solid to liquid state at its meliting point without change in its temperature is clled it latent heat of fusion
Question: 44
What is meant by internal energy of a body
Answer: 44
44-116The sum of potential energy and Kinetic energy associated with atoms, molecules and particles of a body is called its internal energy
Question: 45
Why is ehat called as the energy in trans it
Answer: 45
45-116Heat is the energy that is transferred from one body to the other in thermal contact with each other as result of the difference of temperature between them The transfer of energy continues till both the bodies have the same temperature Heat is therefore called as the energy in trans it
Question: 46
Why gaps are left in railways tracks
Answer: 46
46-116Gaps are left in railway tracks to compensate thermal expansion during hot season Because in summer railway tracks expand due to increase in temperature.
Question: 47
How can Celsius scale be converted into Kelvin and Fahrenheit scales
Answer: 47
47-116Celsius to Fahrenheit scale: The temperate T on Kelvin scale be obtained by adding 273 in the temperature C on Celsius scale Thus
Question: 48
What is clinicl thermometer
Answer: 48
48-116A clinical thermometer is used toi measure the temperature of human body It has a narrow range from 35 C to 42 C It has constriction that prevents the mercury to return Thus its reading does not change until reset
Question: 49
What is the use of thermometer
Answer: 49
49-116Thermometer: A thermometer is a device which is used to measure the temperature of a body mercury is preferred as a thermometric substance due to following properties.
It is easily visible
It has uniform thermal expansion
It has low freezing point and ight boiling point
It has a small specific heat capacity.
Question: 50
Which flower is used as natural thermometer
Answer: 50
50-116The crocus flower is a natural thermometer It opens when temperature is precisely 23 and closes Ehen temperature drops
Question: 51
Why wet clothes dry up more quickly in summer then winter
Answer: 51
51-116Wet clothes dry up more quickly in summer then winter because there is high temperature in summer due to which process of evaporation becomes speedy which process of evaporation becomes speedy
Question: 52
Define latent heat of vaporization
Answer: 52
52-116The quantity of heat that changes unit mass of a liquid completely into gas at its boiling point without any change in its temperature is called latent heat of vaporization
Question: 53
What is absolute zero
Answer: 53
53-116Absolute zero: Absolute zero is equal to 273c The change in temperature is equal in =
Question: 54
What are the factors on which internal energy depends upon
Answer: 54
54-116Internal energy of a body depends upon
Mass of body
Kinetic energyh of a body
Potential energy of a body
Question: 55
Define thermometer and write its types
Answer: 55
55-116Thermometer: A thermometer is a device which is used to measure the temperature of a body Mercury is preferred as a thermometric substance due to following properties.
Question: 56
Differentiate between freezing and melting point
Answer: 56
56-116Freezing point: In liquids the point of temperature which liquids starts to become solids
Freezing point is that point which liquids starts to become solids
Water starts to become ice at temperature.
Question: 57
Write a note on centigrade scale
Answer: 57
57-116On centigrade scale the interval between lower and upper fixed pints is divided into 100 equal part
Lower fixed point, upper fixed point is 100
Question: 58
Write two factors on which evaporation dpends
Answer: 58
58-116Factors;
Temperature: At hewer temperature, more molecules of a liquid are moving with high velocities Evaporation is faster at high temperature then at low temperature.
Question: 59
How temperature affects evaporation
Answer: 59
59-116As temperature increases rate of evaporation also increases because on increasing temperature average kinetic energy of liquid molecules increases and there are more chances for molecules to escape out of liquid surface.
Question: 60
How evaporation differs from vaporization
Answer: 60
60-116Evaporation is differs from vaporization because evaporation takes places from the surface of liquid at all temperatures. But vaporization takes place at a fixed temperature or boiling point
Question: 61
Write the value of latent heat of fusion not aluminum and copper
Answer: 61
61-116Latent heat of fusion of Aluminum is 39.7 kg kg of leant heat of fusion of copper is
Question: 62
How many intervals are in Kelvin scale
Answer: 62
62-116In Kelvin scale the interval between lower and upper fixed points is divided into 100 equal parts.
Lower fixed point = 273
Upper fixed point = 373
Question: 63
Define Latent Heat of fusion?
Answer: 63
63-116Heat energy required to change unit mass of a substance from solid to liquid state at it's melting point without change in the temperature is called latent heat of fusion.
Question: 64
How wind affects evaporation
Answer: 64
64-116Wind blowing over the surface of a liquid sweeps away the liquid molecules that have just escaped out it thus stops these molecules from returning to the liquid which increases vaporization
Question: 65
What is meant by linear thermal expansion
Answer: 65
65-116If length of solid changes with change in temperature is called linear thermal expansion
Question: 66
Differentiate between heat and Internal energy
Answer: 66
66-116Heat: Heat is form of energy which transferred from one body to the other in thermal contact with each other as a result of difference of temperature between them
Question: 67
Define coefficient of linear thermal expansion
Answer: 67
67-116Coefficient of linear thermal expansion can be defined as fractional increase in length per kelvin rise in temperature.
Question: 68
Write two charactersticws of the liquid used in thermometer
Answer: 68
68-116Common thermometers are generally made using some suitable liquids as thermometric material A thermometric liquid should have following characteristics
It should be visible
It should have same heat temperature
It should have low freezing point and high boiling point
Question: 69
Define heat capacity of a body
Answer: 69
69-116Heat capacity of a body is amount of thermal energy absorbed by it for one Kelvin rise in temperature.
Question: 70
Describe relation between heat capacity and quantity of substance
Answer: 70
70-116Relation: Heat Capacity mass
Larger is the quantity of a substance larger will be its heat capacity
Question: 71
What is a relationship between the coefficient of linear and bolume expansion
Answer: 71
71-116The coefficient of linear and volume expansion are related by the equation
B=3a
Question: 72
Define Evaporation
Answer: 72
72-116Evaporation is the changing of a liquid into vapors (gaseous start) from the surface of the loiquid without heating it
Question: 73
What is meant by latent heat of fusion
Answer: 73
73-116Latent heat of fusion: Heat energy required to change unit mass of a substance from solid to liquid stte at its melting point without change it its temperature is called its latent heat of fusion denoted by
Question: 74
Explain anomalous expansion of water
Answer: 74
74-116Water on cooling below 4 C begins to expand until it reaches 0 C On further cooling its volume increases suddenly as it changes into ice at 0 C When ice is cooled below 0 C it contract i.e its volume decreases like solids. This unusual expansion of water is called anomalous expansion of water
Question: 75
Write the scales of temperature?
Answer: 75
75-116Mercury in glass thermometers are widely used in laboratories clinics and house to measure temperature in the range from -10°c to 150°c.
Question: 76
Write any two uses of thermal expansion in our daily life
Answer: 76
76-116Expansion of railway track: Railway tracks buckled on a hot summer day due to expansion if gaps are not left between sectioins
Question: 77
Does water nd spirit evaporate at same rate
Answer: 77
77-116As nature of liquid affect evaporation So answer is no rate of evaporation for spirit is greater than water due to its weak intermolecular forces. While rate of evaporation for water is relatively slow due to strong hydrogen bonding
Question: 78
What is meant by bimetallic strip
Answer: 78
78-116Bimetallic strip: Bimetallic strip is strip which is consists of two different metals, usually brass and iron.
Question: 79
How cooling is produced in refrigerator
Answer: 79
79-116Cooling is produced in refrigerators by evaporation of a liquefied gas. This produce cooling effect. Freon, a CFC, was used as a refrigerant gas. Bus its use has been forbidden when it was known that CFC is the cause of ozone depletion in the upper atmosphere which results increase in amount of UV rays from the Sun. The rays are harm ful to all living matter Freon gas is now replaced by Ammonia and other substances which are not harmful to the environment
Question: 80
How specific heat differs from heat capacity
Answer: 80
80-116Specific heat: Specific heat of substance is amount of heat require to raise temperature of 1 kg of threat substances mass of that substance through 1k
Question: 81
Define lower and upper fixed points
Answer: 81
81-116Lower fixed point: The lower fixed point is marked to show the position of liquid in the mometer when it is placed in ice.
Question: 82
Define convection?
Answer: 82
82-116Transfer of heat by
Question: 83
Write equation of conversion from Kelvin scale to Celsius scle
Answer: 83
83-116The equation of conversion from Kelvin scale to Celsius scale is given below
C=t(k
Question: 84
What is the thermos flask?
Answer: 84
84-116A thermos flask consists of a double-walled glass vessel.
Question: 85
Write the use and range of clinical thermometer
Answer: 85
85-116Clinical thermometer: A clinical thermometer is used to measure the temperature of human body It has a narrow range from
Question: 86
What is meant by anomalous expansion of water
Answer: 86
86-116Water on cooling below 4c begins to expand until it reaches further cooling its volume increases suddenly as it changes into ice at When ice is cooled below it contracts i.e. its volume decreases like solids. This unusual expansion of water is called the anomalous expansion of water
Question: 87
Write names of types of thermal volume expansion for liquids
Answer: 87
87-116Types of thermal volume expansion for liquids are
Real volume eapansion,
Apparent volume expansion
Question: 88
What are Kelvin scale and Fahrenheit scale
Answer: 88
88-116Fahrenheit scale: On Fahrenheit scale, the interval between lower and upper fixed points is divided into 180 equal parts Its lower and upper fixed points are and respectively
Question: 89
Write names of two scales of measuring temperature
Answer: 89
89-116There are three scales of measuring temperature.
Celsius scale
Fahrenheit scale
Question: 90
How temperature determines the direction of flow of heat
Answer: 90
90-116Temperature determines the direction of flow of heat as it flows from a hot body to a cold body until thermal equilibrium is reached
Question: 91
Define Coefficient of linear thermal expansion and what is its SI unit
Answer: 91
91-116Co-efficient of linear thermal: Co-efficient of linear thermal expansion of substance can be defined and fractional increase in its length per Kelvin rise in temperature.
Question: 92
What is the effect of surface area on the evaporation
Answer: 92
92-116The rate of evaporation is affected by surface area that larger is the surface area of liquid greater number of molecules escape from its surface therefore, water evaporates faster when spread over larger area and the process become fast.
Question: 93
Write the use and range of chemical thermometer?
Answer: 93
93-116A clinical thermometer is used to measure the temperature of human body .
Question: 94
What is meant by specific heat
Answer: 94
94-116Heat capacity: Heat capacity of a body is the quantity of a thermal energy absorbed by it for one kelvin increase in its temperature.
Question: 95
On what factors, radiation depends?
Answer: 95
95-1161- Colour and texture of the surface
2- Surface temperature
3- Surface area
Question: 96
Define temperature
Answer: 96
96-116Temperature: Temperature of a body is the degree of hotness or coldness of the temperature is a scalar quantity
Question: 97
Define internal energy
Answer: 97
97-116Internal Energy: The sum of kinetic energy and potential energy associated with the atoms molecules and particles of a body is called its internal energy
Question: 98
What is the effect of temperature on evaporation.
Answer: 98
98-116At high temperature more molecules of a liquid are moving with high velocities. Thus more molecules are escaping from its surface The evaporation is faster at high temperature than at low temperature.
Question: 99
Why liquids expand on heating
Answer: 99
99-116On heating a liquid average amplitude of vibration of molecules increases molecules push each other and need more space to occupy Thus causes the expansion of liquids on eating
Question: 100
Write down the values of coefficient of Gold and Silver
Answer: 100
100-116Co-efficient of = God 1.3*10k
Co-efficient of = Silver 1.93*10
Question: 101
Does water and spirit evaporate at the same rate
Answer: 101
101-116Evaporation rate of different liquids are different Water and spirit evaporate at different temperature. Form example put a few drops of spirit on hand Drops of spirit will evaporate quickly and the same action will not happen with water The reason is this that the boiling point of spirit lesser than the boiling point of water That is why both spirit water do not evaporate at the same rate
Question: 102
Difference between conductor and nonconductor?
Answer: 102
102-116Conductors can pass the heat and electricity, but non conductors are not capable of doing this
Question: 103
Why water is used in cooling system of vehicles
Answer: 103
103-116Due too large specific heat capacity of water it is very useful in storing and caring thermal energy So it is used in cooling system of vehicles to carry large amount of thermal energy
Question: 104
Give the names of factors on which evaporation of a liquid depends
Answer: 104
104-116The rate of evaporation is affected by following factors
Temperature, Surface area, wind , nature of liquid
Question: 105
Why heat is transferred from hot body to cold body
Answer: 105
105-116Take two bodies having different temperature Bring them in contact with each other The temperature of hot body falls It losses energy The engery enters the cold body at lower temperature hus energy transfers from hot body to cold body in the form of heat
Question: 106
What is the difference between linear thermal expansion and volume thermal expansion
Answer: 106
106-116Linear Thermal Expansion: The increase in the length of a solid on heating is called linear thermal expansion
The co-efficient of linear thermal expansion is and its value is
In any solid material or body the value of a is one third of that b
Question: 107
Why gaps are left in railway tracks
Answer: 107
107-116Gaps are left in railway tracks to compensate thermal expansion during hot season otherwise they will break due to expansion.
Question: 108
What is meant by thermal expansion
Answer: 108
108-116Thermal Expansion: If change in temperature cause the change in length, or volume of a substance then it is called as thermal expansion of that substance.
Question: 109
Define thermal equilibrium
Answer: 109
109-116Temperatures are brought close to each other the heat is released by hot body and is absorbed by cold body which brings them at equal temperature This is called thermal equilibrium
Question: 110
Why bottoms of cooking pots are made black?
Answer: 110
110-116The bottoms ofcoking pots are made black to increase the absorption of heat from life
Question: 111
What is meant by conduction?
Answer: 111
111-116The mole of transfer of heat by vibrating atoms and free electrons in solids from a hot to cold parts of a body is called conduction of heat.
Question: 112
Write the names of types of thermal volume pension for liquids
Answer: 112
112-116There are two types of thermal volume
Appearing volume expansion, Real volume expansion.
Question: 113
Why our clothes dry up more quickly in summer than in winter
Answer: 113
113-116Clothes dry up more quickly in summer than in winter because in summers temperature is high which inreases the rate of evaporation.
Question: 114
Define volume thermal expansion and temperature co-efficient of volume expansion
Answer: 114
114-116Volume thermal expansion: Solid material expend in volume when heated. This process is called volume thermal expansion.
Question: 115
We near white and light colored clothes in summer why?
Answer: 115
115-116During summer most of people preferto wear awhite dress because white reflects lights . So its order to keep your body temperature normal it, s better to wear awhite dress
Question: 116
What is difference between temperature and heat
Answer: 116
116-116Heat: Heat is form of energy which transferred from one body to the other in thermal contact with each other as a result of difference of temperature between them
