Heat
1 Marks Question
- On what factors do the quantity of heat of an object depend?
- The quantity of heat of an object depends on the mass of an object, specific heat capacity and difference in temperature.
- Write the relation between heat gain or loss by a body with its surface area.
- The larger the area exposed to the surrounding higher will be the loss of heat and vice versa.
- What is heat equation?
- The heat equation states that the quantity of heat lost or gained by a body is equal to the product of mass, specific heat capacity and temperature difference of the body. That is, Q = m.s.dt
- Write the boiling point and freezing point of mercury.
- The boiling point 357°C is and freezing point is -39°C.
- Define heat in terms of kinetic energy of molecules.
- The sum of kinetic energy contained by the molecules of an object is called heat.
- What is specific heat capacity?
-
The amount of heat required to raise or decrease the temperature of 1 kg of
a substance by 1°C is called specific heat capacity. Its unit is J/kg°C.
More info: The value of specific heat capacity of water is 4200 J/kg°C, Oil is 2000 J/kg°C, sand is 800 J/kg°C.
- Write the name of any two thermometric liquids.
- The name of any two thermometric liquids is alcohol, and mercury.
- What are the boiling point and freezing point of alcohol at normal pressure?
- The boiling point of alcohol is 78°C and the freezing point is -117°C at normal pressure.
- Define heat energy.
- The energy that flows from a hotter body to another body producing the sensation of hotness and coldness is called heat energy.
- Define one calorie heat.
- One calorie of heat is defined as the amount of heat required to raise the temperature of 1 gm of pure water by 1°C.
- What is the boiling point of water in Kelvin unit?
-
The boiling point of water in Kelvin unit is 373 K.
More info: The boiling point of water in Celsius unit is 100°C and in Fahrenheit unit is 212°F.
- What is the normal body temperature of a healthy human on the Fahrenheit scale?
-
The normal body temperature of a healthy human on a Fahrenheit scale is
98.6°F.
More info: In Celsius is 37°C and in Kelvin scale is 310 K.
- Name the instrument which is made on the basis of expansion of heat.
- Thermometer is made on the basis of expansion of heat.
- What does it mean by the specific heat capacity of a substance is 140 J/kg°C?
- It means that 140 joules of heat energy are required to raise or decrease the temperature of 1 kg by 1°C temperature.