Calorimetry Questions and Answers

Equal masses of two different liquids are put into identical beakers Liquid 1 is heated for 100s and liquid 2 is heated for 200s by heaters of the same power Each liquid has the same rise in temperature liquid 1 heating time 100s different liquids of same mass heating time 200 s Which statement is correct A Each beaker of liquid has the same thermal capacity B Each beaker of liquid receives the same energy liquid 2 C Liquid 1 receives more energy than liquid 2 D The thermal capacity of liquid 1 is less than the thermal capacity of liquid 2

b Ice cubes of total mass 70g and at 0 C are put into a drink of lemonade of mass 300 g All the ice melts as 23500J of thermal energy transfers from the lemonade to the ice The final temperature of the drink is 0 C i Calculate the specific latent heat of fusion for ice specific latent heat of fusion 2 ii The thermal energy that causes the ice to melt is transferred from the lemonade as it cools The loss of this thermal energy causes the temperature of the 300g of the lemonade to fall by 19 C Calculate the specific heat capacity of the lemonade

7 A block of ice at 20 C is heated until it turns to steam The graph of temperature against thermal energy absorbed is shown The latent heat of fusion of ice is 340 kJ kg 100 80 60 40 20 temperature C 0 20 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400 2600 126 kJ What is the mass of the ice A 1 0kg B 2 0 kg 1146 kJ C 3 0kg thermal energy absorbed kJ D 4 0kg 2406 kJ

2 A ball of thermal capacity 10 cal C is heated to the 22 10 ure the va temperature of furnace It is then transferred into a vessel containing water The water equivalent of vessel and the contents is 200 gm The temperature of the vessel and its contents rises from 10 C to 40 C What is the temperature of furnace 1 640 C 2 64 C 1 640 C 3 600 C way 200 m 1040 contents Ara Harga 2 64 C 4 100 C

water and ice are 4200 J kg C and 2100 J kg C respectively specie latent heat of fusion of ice is 330 kJ kg and thermal conductivity of it is times of that of water Hent capacity of the pistons and that of the pipe negligible The left and the right pistons are maintained at constant temperatures steady state is reached what will the distance between the pistons 40 C and 16 C respectively After a sufficiently long time when a ecome 80 5 cm b 84 2 cm CHLOR

58 An electric kettle takes 4 A current at 220 V How much time will it take to boil 1 kg of water from temperature 20 C The temperature of boiling water is 100 C AIPMT Prelims 2008 1 4 2 min 2 6 3 min 8 4 min 4 12 6 min

A mixture of 100 gm of ice 200 gm of water at 0 C is kept in a copper vessel of water equivalent 70 gm If steam at 100 C is passed through mixture find the amount of steam vaporized till final temperature of mixture becomes 100 C Given L 8 cal gm Ly 540 cal gm 370

Steam at 100 C is passed into 20g of water at 10 C When water acquires a temperature of 80 C the mass of water present will be Take specific heat of water 1cal g C and latent heat of steam 540 cal g 10 8 1 24 g 2 31 5g 3 42 5 g 4 22 5g

Water of volume 2 L in a container is heated with a coil of 1 kW at 27 C The lid of the container is open and energy dissipates at rate of 160 J s In how much time temperature will rise from 27 C to 77 C 2005 2M Specific heat of water is 4 2 kJ kg a 8 min 20 s c 7 min b 6 min 2 s d 14 min

You have two identical small calorimeters and a very accurate thermo meter In one calorimeter is 100 g water at room temperature and in the other is 100 g boiling water If you put the thermometer in the first calorimeter it shows 20 00 C When you remove the thermometer from the first calorimeter and put it in the other it shows 99 20 C If you remove the thermometer from the second calorimeter and immediately put it again in the first one how much would it read Neglect loss of heat to the environment A 20 79 C zzg

Steam at 100 C is allowed to pass into a vessel containing 10g of ice and 100g of water at 0 C until all the ice is melted and the temperature is raised to 50 C Neglecting water equivalent of the vessel and the loss due to radiation etc Calculate how much steam is condensed

Calculate the amount of heat energy required to change 0 713 kg of water at a temperature of 50 C to steam at a temperature of 170C specific heat capacities of ice water and steam are 2090 4180 2010 J kg C respectively Latent heat of fusion and vaporization of water are 3 34e5 2 26e6J kg respectively 1 point JJ 990684 183 J KK 1486658 147 J LL 3008965 313J MM 1860716 1J

30 Choose the correct graph of the variation of specific heat capacity of water with temperature 1 005 1 Specific heat Calg C 2 1004 1000 heal Calig C 0 995 Specific heat Calg C Specific heat Calg C 1 005 1 004 1 000 0 996 1 008 1 004 1 000 0 996 1 008 LUCT 20 Temperature Ch 20 40 40 20 Temperature C 40 1 Temperature C 60 60 ec J 80 80 80 190 100 100

2 26 On an X temperature scale water freezes at 125 X and boils at 375 X On a Y temperature scale water freezes at 70 Y and boils at 30 Y The value of temperature on X scale equal to the temperature of 50 Y on Y scale is X

The cooling curves 1 and 2 of two liquids of same mass Sp heats S and S are cooled under identical conditions as shown in the graph Then A S S B S S Mark For Review Next Save Next PHYSICS 101 102 103 104 105 106 111 112 113 114 115 116 121 122 123 124 125 126 Clear Response Submit 107 108 109 110 117 118 119 120 128 139

Choose the correct statement A Steam causes more severe burns than water at 100 C B In extinguishing fire hot water is preferred to cold water C Ice at produces more cooling than water at 0 C D All the above Mark For Review Next Save Next Clear Response Submit

A clock with a metal pendulum beating seconds keeps correct time at 0 C If loses 12 5 s a day at 25 C the coefficient of linear expansion of metal pendulum is D C 86400 1 43200 C 1 14400 C C 28800

2 Under which of the following conditions resistance of a cylindrical specimen of an Ohmic material is least affected by small temperature variations a Temperature coefficient of resistivity is greater than that of linear expansion b Temperature coefficient of resistivity is lesser than that of linear expansion c Temperature coefficient of resistivity is equal to that of linear expansion d Temperature coefficient of resistivity is negligible as compared t that of linear expansion

3 40 4 120 If a thermometer reads freezing point of water as 20 C and boiling point as 150 C how much thermometer read when the actual temperature is 60 C 1 98 C 2 110 C 3 40 C 4 60 C The distance covered by a body to come to rest 18 19 3 40 160 C 1 98 C 3 40 C 4 120 20 C fees and and a visite 2 110 C 4 60 C 150 C BERGF4ms

Two cylindrical rods each of length L are joined in parallel Their thermal conductivity are and k Their circular area of cross section are A and 2A respectively The equivalent coefficient of thermal conductivity is 1 K K 2 3 K K 2 k 2k 4 k 2k 3

15 A small block of copper with a specific of 100 calories C is initially at a temperature of 540 C It is ther dropped into a large on entropy of the combined system after equilibrium is established JNU 2011 JNU 2013 16 a Decreases by 100 calories K c Decreases by 270 calories K b Increases by 171 calories K d Increases by 70 calories K Identify the correct statement a The entropy of a system always increases when it undergoes an irreversible process

c x 18 Two substances A and B of equal mass m are heated under similar conditions A graph between temperature and time is shown in at uniform rate of 6 cal s by them for figure Ratio of heat absorbed complete fusion is 9 a Temperature C 100 80 60 40 20 0 1 2 3 4 5 b 4 c HB 6 24 5 A 7 B Time d 8

17 Which of the following phenomenon gives evidence of the molecular motion 1 Brownian motion 2 Diffusion 3 Evaporation 4 All of these 18 Volume versus temperature graph of two mole of helium gas is as shown in figure The ratio of change in internal energy and the work done by the gas in process 1 2 is 3 11 2 20 3 5 27 2 1 19 The efficiency of the reversible heat engine is 1 and that of irreversible heat engine is n Which of the following is correct 1 n 1 and n 1 2 1 3 n 1 and n 1 4 1 1 20 Temperature of a body is slightly more than the temperature of the surrounding 0 its rate of cooling R versus temperature of body 0 is plotted its shape would be as per Newton s of cooling R 3 2 3 2 73 4 21 The specific heat of substance varies with temperature 7 as S 0 20 1 47 cal gm C Heat required to raise the temperature of 2 gm of the substance from 5 C to 25 C is T is in C 1 848 cal 3 336 cal 22 Expansion of liquid on heating is different from that solids since expansion of liquid is 24 1 More than solids because molecular spacing in them is less 2 More than solids because molecular spacing in them is more 3 Less than solid because molecular spacing in them is more 4 Less than solids because molecular spacing in them is less 23 A body of mass 25 g is under water at a depth of 50 cm If the specific gravity of material of body is 5 the work necessary to lift the body slowly to the surface is g 9 8 m s 1 980 x 105 erg 3 980 x 10 erg ole Charge Q is distributed on two metallic spheres having radii R and 3R such that both spheres have equal charge density then charge on smaller sphere 1 2 424 cal 4 672 cal 2 3 Ca Charge is distributed non uniformly in a volume of solid insulating sphere of radius a such that volume charge density p varies with distance from the centre r as p r Cr r a and C is constant Magnitude of electric field strength outside the sphere at a distance r from centre will be 55 5 Ca 2 9 8 x 105 erg 4 98 x 105 erg 45 4 Gla 10Q

If we plot a graph having temperature in C on X axis and in F on Y axis then the shape is a straight line The correct statement is A The line intercepts the positive X axis at 32 C B The line intercepts the positive Y axis at 32 F C The line passes through origin D The line intercept the negative axis of both X and Y axes

An aluminium sphere of 100 ce volume is heated from 0 C to 100 C Its volume changes by given that coefficient of linear expansion for aluminium a AI 20 10 6PC O 0 25 cc O 0 2 cc O 20 cc 0 6 cc

Which of the following statement s is are correct B C D Boiling point of ordinary water is greater than heavy water Temperature of maximum density for ordinary water is greater than heavy water Viscosity of ordinary water is greater than heavy water All of these

A hot vanadium solid cylinder weighing 30 kg is submerged in an insulating bath holding 50 L of heavy oil The vanadium cylinder and the oil are allowed to equilibrate thermally without exchanging heat with the surroundings Initially the vanadium cylinder and the oil are at 800 C and 25 C respectively What is the final temperature in C of the vanadium cylinder and the oil Data Vanadium p 6100 kg m3 c 0 49 kJ kg K Oil p 890 kg m3 c 2 1 kJ kg K Conversion 1000 L 1 m3

2 26 An electric heater is used in a room of total wall area 137 m to maintain a temperature of 20 C inside it when the outside temperature is 10 C The walls have three different layers materials The innermost layer is of wood of thickness 2 5 cm the middle layer is of cement of thickness 1 0 cm and the outermost layer is brick 25 0 cm The power of the electric heater will be W Assume that there is no heat loss through the floor and the ceiling The thermal conductivities of wood cement and brick are 0 125 150

C 0 D 36 7 Q 13 The molar specific heat C of a diatomic gas is equal to 2 R IN DIN DIN OT BY R C R D R d oult R 7 6 CF JUN Ved Q 13 fe C R D 36 7 44 A R MIN SI TN alr B R C 7 D R

SolveLancer Test A liquid at room temperature is placed in a small bucket of pure copper The bucket is of 700 g and liquid is of 350 g in bucket In 8 minutes liquid temperature rises to 75 C by flow of 1A current in the coil attached with bucket Assume no heat loss the value of applied voltage is Given Room temp 25 C specific heat of liquid 1 2 cal g C Specific heat of copper 0 1 cal g C SolveLancer Test a 214 V b 170 V c 320 V d 155 V

Find the result of mixing 10 for ice at 10 C with 10 g of water at 10 C Specific heat ca pacity of ice 2 1 J g K specific latent heat of ice 336 J g and specific heat capacity of water 4 2 J g K

i 3 5 kg of fuel was completely burnt The heat produced was measured to be 1 75 000 kJ Calculate the calorific value of the fuel ii Anu wants to boil water quickly in a test tube Which zone candle flame is the best for boiling water and why

Two containers A and B are connected by a conducting solid cylindrical rod of 242 cm length and 7 radius 8 3 cm Thermal conductivity of the rod is 693 watt mole K The container A contains two mole of oxygen gas and the container B contains four mole of helium gas At time t 0 temperature difference of the containers is 50 After what time in seconds temperature difference between them will be 25 Transfer of heat takes place through the rod only through conduction Neglect radiation loss Take R 8 3J mole K 22 7 In 2 0 693

For water to go through a phase change its temperature must be greater than or equal to 212 F or less than or equal to 32 F If a glass of water is currently at 67 F what temperature changes will produce a phase change O 35 x 145 O 35 x 145 Ox 35 or x 145 O x 35 or x 145

A block of ice at 0 C was being heated at a constant rate The volume of sample as a function of time is shown in the graph below Take Pice 0 9 gm cc Pwater 1 gm cc Ywater 10 C Specific heat capacity of water 1 cal gm C latent heat of fusion of ice 80 cal gm V 100cd V A V 90 cc C tan 0 1 44 cc min 5 min dH B 24 cal sec dt D Water will start boiling at 8 24 min

A liquid at 30 C is poured very slowly into a Calorimeter that is at temperature of 110 C The boiling temperature of the liquid is 80 C It is found that the first 5 gm of the liquid completely evaporates After pouring another 80 gm of the liquid the equilibrium temperature is found to be 50 C The ratio of the Latent heat of the liquid to its specific heat will be C Neglect the heat exchange with surrounding

1 The mass of a calorimeter is 10 gm The specific heat of the material of the calorimeter is 0 1 It contains 49 gm of water at 25 C 10 gm of ice is dropped in the water in the calorimeter Latent heat of ice is 80 cal gm the final temperature of the water in the calorimeter is A 5 0 C B 7 5 C C 11 5 C D 15 0 C

3 1600 gm 1 3 13 Work done in converting 1g of ice at 10 C into steam at 100 C is 1 3 04 kJ 2 6 05 kJ 3 0 721 kJ 4 0 616 kJ am of steam condenses when passed through 40 gm of water initially at 25 C The condensation of st Intont heat of steam

Three identical rods of length 1m each having cross section area of 1cm each and made of Aluminium copper and steel respectively are maintained at temperatures of 12 C 4 C and 50 C respectively at their separate ends Find the temperature of their common junction Kc 400 W m K K 200 W m K Ksteel 50 W m K Cu Al 12 C Aluminium steel 50 C copper

3 A series resistance of series generator is 1 ohm In driving a certain load at 1200 rpm the current drawn by the generator is 25A from a voltage source of V 440Vpc The rotational loss is 250W Find the input power and efficiency 1 HP 0 746 kW

I take 1kg of ice at 0 degrees Celcius and I dump it into 1kg of water at 20 degrees Celsius If the heat capacity of the container is neglected what is the equilibrium temperature Lf 79 8 kcal kg Cw 1 kcal kg Celsius Choices a 10 degrees Celsius b 0 degrees Celsius c 59 8 degrees Celsius d 5 degrees Celsius e The equilibrium cannot be determined

A 66 34 g cube of iron at 100 C is placed in coffee cup calorimeter containing a 129 8 g sample of mercury at 0 00 C What is the final temperature of the iron Answer C Give your answer to the hundredths place

An L shaped rod of mass M is free to rotate in a vertical plane about the axis AA It is released from the position shown in the figure The maximum angular acceleration of the rod during motion is A A l

1 At a depth of 1000 m in an ocean what is the gauge pressure The density of sea water is 1 03 x 10 kg m g 10 m s P Rgh 1 1 03 x 105 Pa 1x105 2 2 06 x 105 Pa 3 1 03 x 107 Pa 4 2 06 x 107 Pa

The thermal capacity of any body is 1 a measure of its capacity to absorb heat 2 a measure of its capacity to provide heat 3 the quantity of heat required to raise its temperature by a unit degree 4 the quantity of heat required to raise the temperature of a unit mass of the body by a unit degree

and latent heat A piece of ice heat capacity 2100 J kg C 3 36 x 105 J kg of mass m grams is at 5 C at atmospheric pressure It is given 420 J of heat so that the ice starts melting Finally when the ice water mixture is in equilibrium it is found that 1 g of ice has melted Assuming there is no other heat exchange in the process the value of mis 1 40 g 2 8 g 3 16 g 4 24 g

2 litre water at 27 C is heated by a 1 kW heater in an open container On an average heat is lost to surroundings at the rate 160 J s The time required for the temperature to reach 77 C is 1 8 min 20 sec 2 10 min 3 7 min 4 14 min

A 2100 W continuous flow geyser instant geyser has water inlet temperature 10 C while the water flows out at the rate of 20 g s The outlet temperature of water must be about 1 20 C 2 30 C 3 35 C 4 40 C

NUMERICAL VALUE TYPE This section contains 8 questions Each question is numerical value For each question enter the correct numerical value in decimal notation truncated rounded off to second decimal place e g 6 25 7 00 0 33 30 30 27 127 30 Marking scheme 3 for correct answer 0 if not attempted and 0 in all other cases 7 A thermally insulated vessel contains some water at 0 C The vessel is connected to a vacuum pump to pump out water vapour This results in some water getting frozen It is given Latent heat of vaporization of water at 0 C 21x10 J kg and latent heat of freezing of water 3 36 105 J kg The maximum percentage amount of water that will be solidified in this manner will be

A piece of ice having temperature 0 C is thrown into a thermally insulated container filled with water of volume 5 dm at a temperature of 50 C Match the final amount of water in the container if after the ice melts the temperature of the system is T C T 15 V 35 19 dm T 0 V 65 8 dm T 5 V 130 17 dm T 10 V 20 9 dm