What is meant by temperature? A) Amount of heat in a body B) Degree of hotness or coldness of a body C) Volume of a body D) Mass of a body Answer: B) Degree of hotness or coldness of a body
The SI unit of temperature is: A) °C B) °F C) K D) Calorie Answer: C) K
Which instrument is used to measure temperature? A) Barometer B) Thermometer C) Hygrometer D) Ammeter Answer: B) Thermometer
Heat is a form of: A) Matter B) Energy C) Force D) Power Answer: B) Energy
Heat flows from: A) Cold body to hot body B) Hot body to cold body C) Higher mass to lower mass D) Lower density to higher density Answer: B) Hot body to cold body
The SI unit of heat energy is: A) Joule B) Watt C) Kelvin D) Newton Answer: A) Joule
One calorie is equal to: A) 2.2 J B) 3.5 J C) 4.2 J D) 5.6 J Answer: C) 4.2 J
Which scale is used in scientific work? A) Celsius B) Fahrenheit C) Kelvin D) Reaumur Answer: C) Kelvin
Absolute zero temperature is: A) 0°C B) –100°C C) –273°C D) 273°C Answer: C) –273°C
The lower fixed point on Celsius scale is: A) Boiling point of water B) Melting point of ice C) Absolute zero D) Room temperature Answer: B) Melting point of ice
The upper fixed point on Celsius scale is: A) Melting point of ice B) Boiling point of water C) Absolute zero D) 50°C Answer: B) Boiling point of water
Convert 25°C into Kelvin. A) 248 K B) 273 K C) 298 K D) 323 K Answer: C) 298 K
The formula for Kelvin temperature is: A) K = °C – 273 B) K = °C + 273 C) K = °C × 273 D) K = °C ÷ 273 Answer: B) K = °C + 273
Which thermometer is used for measuring human body temperature? A) Laboratory thermometer B) Clinical thermometer C) Mercury barometer D) Alcohol thermometer Answer: B) Clinical thermometer
Normal human body temperature is: A) 35°C B) 37°C C) 40°C D) 42°C Answer: B) 37°C
Heat capacity depends upon: A) Material and mass B) Shape only C) Color only D) Pressure only Answer: A) Material and mass
Specific heat capacity is the heat required to raise the temperature of: A) 1 kg of substance by 1 K B) Entire body by 1 K C) 1 m³ of substance by 1 K D) 1 g of substance by 10 K Answer: A) 1 kg of substance by 1 K
SI unit of specific heat capacity is: A) J/kg·K B) N/kg C) W/kg D) J/K Answer: A) J/kg·K
Water has a very: A) Low specific heat capacity B) High specific heat capacity C) Zero specific heat capacity D) Negative specific heat capacity Answer: B) High specific heat capacity
Formula for heat energy is: A) Q = mcΔT B) Q = mv C) Q = ma D) Q = Pt Answer: A) Q = mcΔT
If m = 2 kg, c = 4200 J/kg·K and ΔT = 5 K, heat absorbed is: A) 21000 J B) 42000 J C) 84000 J D) 10000 J Answer: B) 42000 J
Thermal expansion means: A) Increase in mass B) Increase in volume due to heat C) Increase in density D) Increase in weight Answer: B) Increase in volume due to heat
Solids expand when: A) Cooled B) Heated C) Pressurized D) Compressed Answer: B) Heated
The expansion of liquids is greater than that of: A) Gases B) Solids C) Vacuum D) Plasma Answer: B) Solids
Which state of matter expands the most on heating? A) Solid B) Liquid C) Gas D) Ice Answer: C) Gas
The coefficient of linear expansion is represented by: A) α B) β C) γ D) λ Answer: A) α
Formula of linear expansion is: A) ΔL = αL₀ΔT B) ΔL = mgh C) ΔL = Fd D) ΔL = IV Answer: A) ΔL = αL₀ΔT
Bridges are provided with expansion joints because: A) To increase strength B) To allow thermal expansion C) To reduce weight D) For decoration Answer: B) To allow thermal expansion
Telephone wires sag more in summer due to: A) Contraction B) Expansion C) Magnetism D) Pressure Answer: B) Expansion
Bimetallic strips work on the principle of: A) Equal expansion B) Unequal expansion C) Reflection D) Refraction Answer: B) Unequal expansion
Which device commonly uses a bimetallic strip? A) Thermostat B) Voltmeter C) Ammeter D) Generator Answer: A) Thermostat
Change of state from solid to liquid is called: A) Condensation B) Evaporation C) Melting D) Sublimation Answer: C) Melting
Melting point of ice is: A) 0°C B) 32°C C) 100°C D) –273°C Answer: A) 0°C
Boiling point of water at standard pressure is: A) 0°C B) 50°C C) 100°C D) 273°C Answer: C) 100°C
Conversion of liquid into gas is called: A) Melting B) Condensation C) Vaporization D) Freezing Answer: C) Vaporization
Conversion of gas into liquid is called: A) Condensation B) Sublimation C) Fusion D) Evaporation Answer: A) Condensation
Heat required to change state without changing temperature is called: A) Sensible heat B) Specific heat C) Latent heat D) Thermal heat Answer: C) Latent heat
Latent heat of fusion is associated with: A) Melting B) Boiling C) Condensation D) Cooling Answer: A) Melting
Latent heat of vaporization is associated with: A) Freezing B) Vaporization C) Condensation D) Sublimation Answer: B) Vaporization
Formula for latent heat is: A) Q = mL B) Q = mcΔT C) Q = Pt D) Q = IVt Answer: A) Q = mL
If 2 kg of ice requires 336000 J/kg latent heat, total heat required is: A) 336000 J B) 672000 J C) 168000 J D) 100000 J Answer: B) 672000 J
Sublimation is the process in which: A) Solid changes directly into gas B) Gas changes into liquid C) Liquid changes into solid D) Gas changes into solid only Answer: A) Solid changes directly into gas
Dry ice is an example of: A) Fusion B) Sublimation C) Condensation D) Freezing Answer: B) Sublimation
Sea breeze occurs during: A) Daytime B) Nighttime C) Winter only D) Rain only Answer: A) Daytime
Land breeze occurs during: A) Day B) Night C) Noon D) Summer only Answer: B) Night
Conduction occurs mainly in: A) Solids B) Liquids only C) Gases only D) Vacuum Answer: A) Solids
Convection occurs mainly in: A) Solids B) Liquids and gases C) Vacuum D) Metals only Answer: B) Liquids and gases
Radiation can travel through: A) Solids only B) Liquids only C) Gases only D) Vacuum Answer: D) Vacuum
The Sun’s heat reaches Earth by: A) Conduction B) Convection C) Radiation D) Diffusion Answer: C) Radiation
Black surfaces are good: A) Reflectors of heat B) Absorbers and emitters of heat C) Conductors only D) Insulators only Answer: B) Absorbers and emitters of heat
Which color is the best absorber of heat radiation? A) White B) Silver C) Black D) Yellow Answer: C) Black
Which color is the best reflector of heat? A) Black B) White C) Red D) Blue Answer: B) White
A thermos flask minimizes heat transfer by: A) Conduction only B) Radiation only C) All three modes of heat transfer D) Convection only Answer: C) All three modes of heat transfer
Vacuum between the walls of a thermos flask prevents: A) Radiation only B) Conduction and convection C) Conduction only D) Expansion Answer: B) Conduction and convection
The silvered surfaces of a thermos flask reduce heat transfer by: A) Conduction B) Convection C) Radiation D) Expansion Answer: C) Radiation
Which is a poor conductor of heat? A) Copper B) Aluminium C) Wood D) Iron Answer: C) Wood
Which is the best conductor of heat? A) Glass B) Wood C) Copper D) Plastic Answer: C) Copper
Cooking utensils are usually made of: A) Plastic B) Iron or Aluminium C) Wood D) Rubber Answer: B) Iron or Aluminium
Handles of cooking pots are made of wood or plastic because they are: A) Good conductors B) Bad conductors C) Heavy materials D) Magnetic Answer: B) Bad conductors
The transfer of heat by actual movement of molecules is called: A) Conduction B) Radiation C) Convection D) Reflection Answer: C) Convection
Hot air rises because it becomes: A) Denser B) Lighter C) Heavier D) Colder Answer: B) Lighter
Winds near sea coasts are caused by: A) Radiation only B) Convection currents C) Reflection D) Refraction Answer: B) Convection currents
Heat transfer without any material medium occurs by: A) Conduction B) Convection C) Radiation D) Diffusion Answer: C) Radiation
Which waves carry radiant heat? A) Sound waves B) Infrared waves C) Water waves D) Radio waves Answer: B) Infrared waves
Radiation travels with the speed of: A) Sound B) Light C) Wind D) Heat conduction Answer: B) Light
Which material is used in thermometers due to uniform expansion? A) Water B) Mercury C) Oil D) Alcohol only Answer: B) Mercury
The range of a clinical thermometer is: A) 0°C–100°C B) –10°C–110°C C) 35°C–42°C D) 10°C–50°C Answer: C) 35°C–42°C
Laboratory thermometers generally measure temperatures from: A) 35°C to 42°C B) –10°C to 110°C C) 0°C to 50°C D) 10°C to 90°C Answer: B) –10°C to 110°C
Which temperature scale has no negative temperatures? A) Celsius B) Fahrenheit C) Kelvin D) Centigrade Answer: C) Kelvin
The boiling point of water on Kelvin scale is: A) 100 K B) 273 K C) 373 K D) 473 K Answer: C) 373 K
Convert 50°C into Kelvin. A) 273 K B) 323 K C) 350 K D) 250 K Answer: B) 323 K
Convert 300 K into Celsius. A) 0°C B) 27°C C) 37°C D) 100°C Answer: B) 27°C
If the temperature rise is doubled, the heat gained becomes: A) Half B) Double C) One-fourth D) Zero Answer: B) Double
The specific heat capacity of water is: A) 2100 J/kg·K B) 4200 J/kg·K C) 8400 J/kg·K D) 1000 J/kg·K Answer: B) 4200 J/kg·K
Heat required to raise the temperature of 1 kg water by 1°C is: A) 2100 J B) 4200 J C) 8400 J D) 1000 J Answer: B) 4200 J
A body of mass 3 kg and specific heat 500 J/kg·K is heated through 20 K. Heat absorbed is: A) 10000 J B) 30000 J C) 15000 J D) 20000 J Answer: B) 30000 J
Formula for heat capacity (C) is: A) C = mc B) C = m/c C) C = c/m D) C = mv Answer: A) C = mc
The unit of heat capacity is: A) J/kg·K B) J/K C) W/K D) N/K Answer: B) J/K
A 2 kg body having specific heat 400 J/kg·K has heat capacity: A) 200 J/K B) 400 J/K C) 800 J/K D) 1000 J/K Answer: C) 800 J/K
During melting, temperature remains: A) Increasing B) Decreasing C) Constant D) Zero Answer: C) Constant
During boiling, temperature remains: A) Constant B) Increasing continuously C) Decreasing D) Negative Answer: A) Constant
The latent heat of fusion of ice is approximately: A) 80 cal/g B) 40 cal/g C) 100 cal/g D) 20 cal/g Answer: A) 80 cal/g
The latent heat of vaporization of water is approximately: A) 540 cal/g B) 80 cal/g C) 100 cal/g D) 420 cal/g Answer: A) 540 cal/g
Which process cools the human body? A) Condensation B) Evaporation of sweat C) Freezing D) Melting Answer: B) Evaporation of sweat
Evaporation occurs at: A) Boiling point only B) Any temperature C) 0°C only D) 100°C only Answer: B) Any temperature
Boiling occurs at: A) Any temperature B) Melting point C) A fixed temperature D) Absolute zero Answer: C) A fixed temperature
Which factor increases evaporation? A) High humidity B) Large surface area C) Low temperature D) Still air Answer: B) Large surface area
Clothes dry faster on a windy day because: A) Pressure decreases B) Evaporation increases C) Temperature decreases D) Gravity increases Answer: B) Evaporation increases
The unit of latent heat is: A) J/kg B) J/K C) W/kg D) N/kg Answer: A) J/kg
If latent heat of vaporization of water is 2.26 × 10⁶ J/kg, heat required to vaporize 2 kg water is: A) 2.26 × 10⁶ J B) 4.52 × 10⁶ J C) 1.13 × 10⁶ J D) 6.78 × 10⁶ J Answer: B) 4.52 × 10⁶ J
Which metal expands most among solids? A) Iron B) Copper C) Aluminium D) Steel Answer: C) Aluminium
Gaps are left between railway tracks to: A) Reduce friction B) Allow thermal expansion C) Increase speed D) Save material Answer: B) Allow thermal expansion
The SI unit of coefficient of linear expansion is: A) m B) m² C) K⁻¹ D) J Answer: C) K⁻¹
In cold weather, electric wires become: A) Longer B) Shorter and tighter C) Melted D) Wider Answer: B) Shorter and tighter
Which mode of heat transfer does not require matter? A) Conduction B) Convection C) Radiation D) Diffusion Answer: C) Radiation
Which process changes gas directly into solid? A) Sublimation B) Deposition C) Fusion D) Vaporization Answer: B) Deposition
Camphor changes directly from solid to gas by: A) Fusion B) Sublimation C) Condensation D) Freezing Answer: B) Sublimation
The SI unit of temperature is: A) °C B) °F C) Kelvin D) Calorie Answer: C) Kelvin
Which property of water helps moderate climate near seas? A) Low density B) High specific heat capacity C) High conductivity D) Low boiling point Answer: B) High specific heat capacity
Which statement is correct? A) Heat and temperature are the same quantities. B) Heat flows from colder to hotter body. C) Heat is energy and temperature indicates degree of hotness. D) Temperature is measured in joules. Answer: C) Heat is energy and temperature indicates degree of hotness.