Define mechanical work done .

Work done is the product of the force applied to an object and the distance over which the force is applied, measured in joules (J).

True or False? Work is done when a force is applied to an object, regardless of whether the object moves or not.

False. Work is done when a force is applied to an object and results in the object's movement over a distance in the direction of the force.

True or False? Work can only be done mechanically.

False. Work can also be done electrically, by heating or by radiation.

True or False? The amount of energy transferred is equal to the work done.

True. The amount of energy transferred (in joules) is equal to the work done (in joules) when any mechanical work is done.

True or False? Work is done on a ball when it is lifted to a height.

True. Work is done on a ball when it is lifted to a height.

Define gravitational potential energy .

Gravitational potential energy is the energy transferred to an object due to its change in height in a gravitational field.

True or False? Energy is transferred away from an object's gravitational potential store when it is lifted.

False. Energy is transferred to an object's gravitational potential store when it is lifted.

True or False? Gravitational potential energy is measured in units of newtons per kilogram (N/kg).

False. Gravitational potential energy is measured in units of joules (J).

True or False? Energy is transferred to an object's gravitational potential store when it falls.

False. Energy is transferred away from an object's gravitational potential store when it falls.

Define kinetic energy .

Kinetic energy is the amount of energy an object has as a result of its mass and speed.

True or False? Any object in motion has energy in its kinetic energy store.

True. Any object in motion possesses kinetic energy.

True or False? Kinetic energy is measured in units of joules per second.

False. Kinetic energy is measured in units of joules (J).

True or False? Energy transfers can be assumed to be perfect (100% efficient) if the wasted energy is negligible.

True. Energy transfers can be assumed to be perfect (100% efficient) if the wasted energy is negligible.

Power is the rate at which energy is transferred or work is done, measured in watts (W).

True or False? Power is the total amount of energy transferred.

False. Power refers to the rate at which energy is transferred or work is done, not the total amount of energy transferred.

True or False? A car has more power if it does the same amount of work in a longer amount of time.

False. A car has more power if it does the same amount of work in a shorter amount of time.

Define the rate of doing work .

The rate of doing work, or power, refers to the amount of work done or energy transferred per unit time. It is measured in watts (W).

True or False? Power and work done are the same quantities.

False. Power is the rate at which energy is transferred or work is done, work done is the total amount of energy transferred.

True or False? Power is often measured in joules (J).

False. Power is typically measured in watts (W), while energy is measured in joules (J).

What are solar cells ?

Solar cells, also known as photovoltaic cells, are devices made of semiconducting materials that produce electricity from sunlight.

True or False? Solar energy is a renewable resource.

True. Solar energy is considered renewable because it is derived from the Sun which is expected to continue shining for billions of years.

What are solar panels ?

Solar panels are devices that transfer energy from sunlight to the thermal store of the panels, which is then used to heat water.

What are the three main fossil fuels?

The three main fossil fuels are: coal oil natural gas (methane)

How do wave and tidal power stations generate electricity?

Wave and tidal power stations generate electricity by utilising the motion of waves or tides to turn turbines, which then generate electricity through electromagnetic induction.

In terms of energy transfers, what is the main purpose of the underwater turbines in wave and tide power systems?

The main purpose of underwater turbines in wave and tide power systems is to transfer energy from the kinetic store of the moving water to the kinetic store of the turbines, which turn generators that generate electricity.

What are hydroelectric dams ?

Hydroelectric dams are structures built across rivers to store water at a height in reservoirs. The water can be released, flowing over a turbine that turns a generator that generates electricity.

What is geothermal energy ?

Geothermal energy is energy stored in the thermal store of rocks beneath the Earth's surface from tectonic heating. The hot rocks are used to heat water that can be used as a hot water supply and to produce steam to turn turbines for electricity generation.

True or False? Geothermal energy is a non-renewable resource.

False. Geothermal energy is considered a renewable resource.

True or False? Solar panels produce greenhouse gases and pollution.

False. Solar panels produce no greenhouse gases or pollution once they are operating.

True or False? Burning fossil fuels produces only carbon dioxide.

False. Burning fossil fuels produces carbon dioxide which is a greenhouse gas that contributes to global warming . But other harmful gases are also released in the combustion of fossil fuels, such as sulphur dioxide which causes acid rain .

What are the main advantages of solar energy?

Advantages of solar energy include: renewable reliable in hot climates produce no greenhouse gases or pollution Can be used in remote areas

What is the main advantage of hydroelectric dams?

The main advantage of hydroelectric dams is their ability to respond to electricity demand quickly and reliably.

What are the main advantages of using biofuels?

The main advantages of biofuels are: renewable carbon neutral

True or False? Nuclear power stations release no pollution into the atmosphere during normal operation.

True. Nuclear power stations do not release pollution into the atmosphere during normal operation.

True or False? Solar farms need to be small-scale to produce large amounts of electricity.

False. Solar farms need to be large-scale to produce significant amounts of electricity.

What is a disadvantage of using fossil fuels?

The disadvantages of using fossil fuels include: non-renewable (so will run out) produce carbon dioxide which contributes to global warming produce sulphur dioxide which causes acid rain

What is the primary advantages of wave and tide power?

The primary advantages of wave and tide power are that they are renewable energy resources that produce no pollution.

What is the main disadvantage of hydroelectric dams?

The main disadvantage of hydroelectric dams is that they require valleys to be flooded. This results in the destruction of habitats, towns, and villages.

What is the primary advantage of geothermal energy?

The primary advantage of geothermal energy is its reliability and renewability . It offers a consistent source of heating and electricity production.

What is the main disadvantage of geothermal energy for electricity production?

The main disadvantage of geothermal energy is the limited availability of suitable locations for large-scale electricity production.

IGCSEPhysicsEdexcelFlashcards4. Energy Resources & Energy TransfersWork, Power & Energy Resources

Work, Power & Energy Resources (Edexcel IGCSE Physics)

Flashcards

1/51

FrontWork Done
Define mechanical work done.
FrontWork Done
What is the formula for calculating work done?
BackWork Done
The formula for calculating work done is $W = F \times d$
Where:
$W$ = work done, measured in joules (J)
$F$ = force, measured in newtons (N)
$d$ = distance, measured in metres (m)

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Cards in this collection (51)

Define mechanical work done.
Work done is the product of the force applied to an object and the distance over which the force is applied, measured in joules (J).
True or False?
Work is done when a force is applied to an object, regardless of whether the object moves or not.
False.
Work is done when a force is applied to an object and results in the object's movement over a distance in the direction of the force.
What is the formula for calculating work done?
The formula for calculating work done is $W = F \times d$
Where:
- $W$ = work done, measured in joules (J)
- $F$ = force, measured in newtons (N)
- $d$ = distance, measured in metres (m)
True or False?
Work can only be done mechanically.
False.
Work can also be done electrically, by heating or by radiation.
True or False?
The amount of energy transferred is equal to the work done.
True.
The amount of energy transferred (in joules) is equal to the work done (in joules) when any mechanical work is done.
State the relationship between energy transferred and work done.
The relationship between energy transferred and work done is:
$energy transferred (J) = work done (J)$
True or False?
Work is done on a ball when it is lifted to a height.
True.
Work is done on a ball when it is lifted to a height.
Define gravitational potential energy.
Gravitational potential energy is the energy transferred to an object due to its change in height in a gravitational field.
True or False?
Energy is transferred away from an object's gravitational potential store when it is lifted.
False.
Energy is transferred to an object's gravitational potential store when it is lifted.
True or False?
Gravitational potential energy is measured in units of newtons per kilogram (N/kg).
False.
Gravitational potential energy is measured in units of joules (J).
What does the term $m$ represent in the gravitational potential energy equation?
In the gravitational potential energy equation, $m$ represents the mass of the object in kilograms (kg).
What is the equation for calculating gravitational potential energy?
The equation for calculating gravitational potential energy is $G P E = m g h$
Where:
- $G P E$ = change in gravitational potential energy
- $m$ = mass, measured in kilograms (kg)
- $g$ = gravitational field strength, measured in newtons per kilogram (N/kg)
- $h$ = height, measured in metres (m)
Define $g$ in terms of the gravitational potential energy equation.
In the gravitational potential energy equation, $g$ represents the gravitational field strength in newtons per kilogram (N/kg).
True or False?
Energy is transferred to an object's gravitational potential store when it falls.
False.
Energy is transferred away from an object's gravitational potential store when it falls.
Define kinetic energy.
Kinetic energy is the amount of energy an object has as a result of its mass and speed.
True or False?
Any object in motion has energy in its kinetic energy store.
True.
Any object in motion possesses kinetic energy.
What is the equation for calculating kinetic energy?
The equation for calculating kinetic energy is $K E = \frac{1}{2} m v^{2}$
Where:
- $K E$ = kinetic energy, measured in joules (J)
- $m$ = mass, measured in kilograms (kg)
- $v$ = velocity, measured in metres per second (m/s)
True or False?
Kinetic energy is measured in units of joules per second.
False.
Kinetic energy is measured in units of joules (J).
What does the term $v$ represent in the kinetic energy equation?
In the kinetic energy equation, $v$ represents the speed of the object in meters per second (m/s).
Define the term $m$ in the kinetic energy equation.
In the kinetic energy equation, $m$ represents the mass of the object in kilograms (kg).
An object has a mass of 2 kg and a velocity of 5 m/s. What is the kinetic energy of the object?
If an object has a mass of 2 kg and a velocity of 5 m/s, then it has 25 J of kinetic energy.
- $K E = \frac{1}{2} m v^{2}$
- $K E = \frac{1}{2} \times 2 \times 5^{2} = 25 J$
True or False?
Energy transfers can be assumed to be perfect (100% efficient) if the wasted energy is negligible.
True.
Energy transfers can be assumed to be perfect (100% efficient) if the wasted energy is negligible.
True or False?
The energy transfers in a pendulum can be equated as $K E_{t o t a l} = G P E_{t o t a l}$ .
True.
The energy transfers in a pendulum can be equated as $K E_{t o t a l} = G P E_{t o t a l}$ .
This kind of energy equivalence is used in lots of calculations involving kinetic and gravitational potential energy.
Define power.
Power is the rate at which energy is transferred or work is done, measured in watts (W).
True or False?
Power is the total amount of energy transferred.
False.
Power refers to the rate at which energy is transferred or work is done, not the total amount of energy transferred.
True or False?
A car has more power if it does the same amount of work in a longer amount of time.
False.
A car has more power if it does the same amount of work in a shorter amount of time.
What is the formula for calculating power?
The formula for calculating power is: $P = \frac{W}{t}$
Where:
- $P$ = power, measured in watts (W)
- $W$ = work done, measured in joules (J)
- $t$ = time, measured in seconds (s)
Define the rate of doing work.
The rate of doing work, or power, refers to the amount of work done or energy transferred per unit time. It is measured in watts (W).
True or False?
Power and work done are the same quantities.
False.
Power is the rate at which energy is transferred or work is done, work done is the total amount of energy transferred.
True or False?
Power is often measured in joules (J).
False.
Power is typically measured in watts (W), while energy is measured in joules (J).
What are solar cells?
Solar cells, also known as photovoltaic cells, are devices made of semiconducting materials that produce electricity from sunlight.
True or False?
Solar energy is a renewable resource.
True.
Solar energy is considered renewable because it is derived from the Sun which is expected to continue shining for billions of years.
What are solar panels?
Solar panels are devices that transfer energy from sunlight to the thermal store of the panels, which is then used to heat water.
What are the three main fossil fuels?
The three main fossil fuels are:
- coal
- oil
- natural gas (methane)
How do wave and tidal power stations generate electricity?
Wave and tidal power stations generate electricity by utilising the motion of waves or tides to turn turbines, which then generate electricity through electromagnetic induction.
In terms of energy transfers, what is the main purpose of the underwater turbines in wave and tide power systems?
The main purpose of underwater turbines in wave and tide power systems is to transfer energy from the kinetic store of the moving water to the kinetic store of the turbines, which turn generators that generate electricity.
What are hydroelectric dams?
Hydroelectric dams are structures built across rivers to store water at a height in reservoirs. The water can be released, flowing over a turbine that turns a generator that generates electricity.
What is geothermal energy?
Geothermal energy is energy stored in the thermal store of rocks beneath the Earth's surface from tectonic heating. The hot rocks are used to heat water that can be used as a hot water supply and to produce steam to turn turbines for electricity generation.
True or False?
Geothermal energy is a non-renewable resource.
False.
Geothermal energy is considered a renewable resource.
True or False?
Solar panels produce greenhouse gases and pollution.
False.
Solar panels produce no greenhouse gases or pollution once they are operating.
True or False?
Burning fossil fuels produces only carbon dioxide.
False.
Burning fossil fuels produces carbon dioxide which is a greenhouse gas that contributes to global warming. But other harmful gases are also released in the combustion of fossil fuels, such as sulphur dioxide which causes acid rain.
What are the main advantages of solar energy?
Advantages of solar energy include:
- renewable
- reliable in hot climates
- produce no greenhouse gases or pollution
- Can be used in remote areas
What is the main advantage of hydroelectric dams?
The main advantage of hydroelectric dams is their ability to respond to electricity demand quickly and reliably.
What are the main advantages of using biofuels?
The main advantages of biofuels are:
- renewable
- carbon neutral
True or False?
Nuclear power stations release no pollution into the atmosphere during normal operation.
True.
Nuclear power stations do not release pollution into the atmosphere during normal operation.
True or False?
Solar farms need to be small-scale to produce large amounts of electricity.
False.
Solar farms need to be large-scale to produce significant amounts of electricity.
What is a disadvantage of using fossil fuels?
The disadvantages of using fossil fuels include:
- non-renewable (so will run out)
- produce carbon dioxide which contributes to global warming
- produce sulphur dioxide which causes acid rain
What is the primary advantages of wave and tide power?
The primary advantages of wave and tide power are that they are renewable energy resources that produce no pollution.
What is the main disadvantage of hydroelectric dams?
The main disadvantage of hydroelectric dams is that they require valleys to be flooded. This results in the destruction of habitats, towns, and villages.
What is the primary advantage of geothermal energy?
The primary advantage of geothermal energy is its reliability and renewability. It offers a consistent source of heating and electricity production.
What is the main disadvantage of geothermal energy for electricity production?
The main disadvantage of geothermal energy is the limited availability of suitable locations for large-scale electricity production.