CGP Topic 4 and 1 (24-30)
Energy Air has a very low
thermal conductivity.
Chemical – stored in food, fuel and batteries Aerogel is a good
Thermal – stored in hot objects insulator as it has a low
thermal conductivity, it is
Kinetic – stored in moving objects
a solid made form silica
Elastic Potential – stored in stretched, squashed objects or carbon framework.
Nuclear – stored in atoms
Mechanical Work Done – transferred when a force is applied over a distance, W=f × d
Gravitational Potential Energy – stored in objects above the ground
Heat Energy – transferred between objects at different temperature
Light energy – can transfer energy via waves even in a vacuum
Sound energy – can transfer via waves in solids, liquids and gas
Electrical potential energy – energy possessed by charged particles within electric fields
Energy cannot be created or destroyed, it can only be transferred from one store to
another
Kinetic energy (type) stored in moving Thermal energy (type) stored in hot
car (object) brakes and road surface (object)
Mechanical work
done by friction
Ask yourself what type of energy is stored in which objects before and after the process and
transferred by which process. Some types of energy are stores of energy, some types act as
energy transfer pro
cesses.
A ball projected upwards:
Kinetic energy in ball GPE in ball
A snooker ball moving horizontal hitting the cushion then rebounding: Kinetic
Kinetic energy in ball Elastic potential energy energy in
Work done
from cushion ball
Chemical energy in food Mechanical
Kinetic energy in car
work done
Boiling water in an electric kettle:
Electrical energy Thermal energy in water
Bullet fired through an egg:
Thermal energy in bullet Thermal energy in egg
Work done
+ +
Kinetic energy in bullet Kinetic energy in egg
, Efficiency
Wasted energy is energy that dissipates into the surroundings and is not useful mechanical processes
become wasteful when they cause a rise in temperature so dissipating energy in heating the surroundings
Efficiency tells us the proportion of energy transferred usefully in a device or process. It can be improved,
in thermal processed, via insulation or lubrication in mechanical processes.
"#$%&' $)$*+, -*.)#%$**$/ 0, /$123$
Efficiency =
45-.' $)$*+, #&66'2$/ 0, /$123$
KE and GPE
𝟏 GPE = mgh
KE = mv2 Kinetic energy – J
𝟐
Mass – Kg
GPE – J
√:;< Velocity – ms-1
V= Mass – kg
=
Gravitational field strength – ms-2
:;< Height - m
M=
1>
Work Done
Force × distance = mass × specific capacity × change in temperature
F × d = mcΔt
Power
?5*@ /5)$ ?
Power = p= Power – watts, w
-2=$ -.@$) - Work done – joules, J
Time – seconds, s
Energy Air has a very low
thermal conductivity.
Chemical – stored in food, fuel and batteries Aerogel is a good
Thermal – stored in hot objects insulator as it has a low
thermal conductivity, it is
Kinetic – stored in moving objects
a solid made form silica
Elastic Potential – stored in stretched, squashed objects or carbon framework.
Nuclear – stored in atoms
Mechanical Work Done – transferred when a force is applied over a distance, W=f × d
Gravitational Potential Energy – stored in objects above the ground
Heat Energy – transferred between objects at different temperature
Light energy – can transfer energy via waves even in a vacuum
Sound energy – can transfer via waves in solids, liquids and gas
Electrical potential energy – energy possessed by charged particles within electric fields
Energy cannot be created or destroyed, it can only be transferred from one store to
another
Kinetic energy (type) stored in moving Thermal energy (type) stored in hot
car (object) brakes and road surface (object)
Mechanical work
done by friction
Ask yourself what type of energy is stored in which objects before and after the process and
transferred by which process. Some types of energy are stores of energy, some types act as
energy transfer pro
cesses.
A ball projected upwards:
Kinetic energy in ball GPE in ball
A snooker ball moving horizontal hitting the cushion then rebounding: Kinetic
Kinetic energy in ball Elastic potential energy energy in
Work done
from cushion ball
Chemical energy in food Mechanical
Kinetic energy in car
work done
Boiling water in an electric kettle:
Electrical energy Thermal energy in water
Bullet fired through an egg:
Thermal energy in bullet Thermal energy in egg
Work done
+ +
Kinetic energy in bullet Kinetic energy in egg
, Efficiency
Wasted energy is energy that dissipates into the surroundings and is not useful mechanical processes
become wasteful when they cause a rise in temperature so dissipating energy in heating the surroundings
Efficiency tells us the proportion of energy transferred usefully in a device or process. It can be improved,
in thermal processed, via insulation or lubrication in mechanical processes.
"#$%&' $)$*+, -*.)#%$**$/ 0, /$123$
Efficiency =
45-.' $)$*+, #&66'2$/ 0, /$123$
KE and GPE
𝟏 GPE = mgh
KE = mv2 Kinetic energy – J
𝟐
Mass – Kg
GPE – J
√:;< Velocity – ms-1
V= Mass – kg
=
Gravitational field strength – ms-2
:;< Height - m
M=
1>
Work Done
Force × distance = mass × specific capacity × change in temperature
F × d = mcΔt
Power
?5*@ /5)$ ?
Power = p= Power – watts, w
-2=$ -.@$) - Work done – joules, J
Time – seconds, s
