P3 e-h revision

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Transcript P3 e-h revision

P3 e-h
LO - To consolidate your
knowledge of the topic
Calculate the GPE and velocity
Fuel Consumption
Fuel consumption is measured in litres per km. (We also
uses miles per gallon as a measure of performance – a
high figure is good.)
Larger vehicles, and those with a greater acceleration
have more powerful engines, so that energy can be
transferred more quickly from the fuel to do work.
When a car brakes, the KE is transferred to heat. Braking
and accelerating repeatedly will transfer more energy
than travelling at a constant speed. The amount of
braking and accelerating will depend on driving style and
the road conditions (e.g. single carriageway, lots of
bends, traffic lights). At higher speeds, resistive forces
are greater and more work is done against friction. If
more energy is transferred the fuel consumption is
increased (increasing cost, and pollution).
1. Why should we aim to reduce carbon dioxide emissions ?
2. Use the table to decide whether there is a connection between carbon
dioxide emissions and the type of fuel used. Explain.
3. Use the table to decide whether there is a connection between carbon
dioxide emissions and the amount of fuel used. Explain.
4. Suggest why more people are buying diesel-powered cars.
• Explain the disadvantages and
advantages of battery-powered cars
Seatbelts, crumple zones, airbags
Reduce injuries
Increase time
taken to stop
force of
How do they work?
Terminal Velocity
Explain in terms of forces, how moving
objects; increase speed, decrease speed
and maintain their speed.
Acceleration due to gravity is the same
For any object at a given
Point on the Earth’s surface