4Th Class Power Engineering-Chapter 18

Front 1

Heat which brings about a change of state:

Back 1

latent heat

Front 2

Radiation from the furnace fire:

Back 2

travels in straight lines

Front 3

A cylindrical tank 0.500 m in diameter and 3.000 m long, is filled with water at a temperature of 15.000 degrees Celsius. Find the quantity of heat required to raise the temperature of the water to 75.000 degrees Celsius. (Use specific heat of water = 4.2 kJ/kg/degree c)

Back 3

148,440.600

Front 4

linear expansion of solid formula?

Change in length=

Back 4

L x coefficient of linear expansion x Change in Temp

Front 5

Define Absolute Pressure:

Back 5

Pressure measured above a perfect vacuum. Atmospheric + gauge pressure.

Front 6

Define Absolute zero:

Back 6

Temp at which molecular motion ceases

Front 7

Define Atmospheric Pressure:

Back 7

Pressure exerted by the earth's atmosphere (101.3 kPa)

Front 8

Define Enthalpy:

Back 8

The amount of heat contained in a substance relative to a base temp at which the enthalpy is defined to be zero (kJ/kg)

Front 9

Define Radiation:

Back 9

transfer of energy by electomagnetic waves

Front 10

Define Sensible Heat:

Back 10

Heat that changes the temp of a substance without changing its state

Front 11

Define Specific Heat:

Back 11

Amount of heat require to raise the temp of a unit of mass of a substance 1C without changing state

Front 12

Define Superheat:

Back 12

Temp increase of a gas or vapour above its saturation temp after all the liquid has been evapourated

Front 13

Define Vacuum:

Back 13

Reduction in pressure below atmospheric pressure

Front 14

First Law of Thermodynamics:

Back 14

Heat and work are mutually convertible:

Heat Supplied = Increase internal energy + Work Done

Front 15

Second Law of Thermodynamics:

Back 15

Unaided heat will flow from hot to cold.

Front 16

Define Temperature:

Back 16

Measure of the speed at which a body's object vibrates

Front 17

3 factors of heat absorption:

Back 17

Temp rise

mass of substance

specific heat of substance

Front 18

Define Liner Expansion:

Back 18

Increase in length due to heating

Front 19

Define coefficient of liner expansion:

Back 19

Change in length per unit length per degree rise in temp

Front 20

Formula for change in Length:

Back 20

Change in length=original length x Coefficient of liner expansion x temp rise