Topic 1- Motion, Forces And Conservation Of Energy Flashcards Preview

Physics > Topic 1- Motion, Forces And Conservation Of Energy > Flashcards

Flashcards in Topic 1- Motion, Forces And Conservation Of Energy Deck (21):
1

8 Energy stores

Kinetic, Thermal, Chemical, Nuclear, Magnetic, Electrostatic, Elastic Potential, GPE

2

Kenton energy depends on...

Mass and speed
Greater the mass and the faster it’s going, the more kinetic energy

3

If you double the mass, the energy in the kinetic energy store...

Doubles

4

If you double the speed, the energy in the kinetic energy store...

Quadruples

5

Energy can be ... , ... between stores and ...
But can never be ... or ...
The total energy of a closed system has...

Stored, transferred and dissipated
Can never be created or destroyed
No net charge

6

Energy can be transferred between stores in four main ways...

Mechanically
Electrically
By heating
By radiation

7

A ball rolling up a slope

The ball does work against the gravitational force
So energy is transferred mechanically from the mentor energy store of the ball to its gravitational potential energy store

8

A bat hitting a ball

Bat has energy in its kinetic energy store
Some out this is transferred mechanically to the balls kinetic energy store
Some is also transferred mechanically to the thermal energy stores of the bat, ball and surroundings
The rest is carried away by sound

9

Energy is only useful when...

It is transferred from one store to a useful store

10

Input energy is always ... and ... to the surroundings

Dissipated or wasted
Often to thermal energy stores

11

When work is done mechanically ... have to be overcome eg.
Therefore...

Frictional forces eg. Things rubbing together and air resistance
Therefore energy needed to overcome this is transferred to thermal energy stores (not useful energy)

12

What reduces unwanted energy transfers

Lubricants- reduce friction between objects when they move usually liquids like oil, can flow easily between objects and coat them
Insulation- between walls of houses, lowest conductivity means slowest rate of energy transferred through them (thick walls and a air gap between the two walls)

13

Non renewable advantages

Reliable- can meet the current demand, use more fuel to release more energy
Cheap to build and run fossil fuel power plants
Low cost of extracting fossil fuels

14

Disadvantages of non renewable

Nuclear power plants cost a lot to build and cause safety issues
Slowly running out
Environmental problems, contribute to global warming
Cause acid rain
Oil spillages
Nuclear waste is dangerous

15

Renewable advantages

Never run out
Not as much impact on environment

16

Disadvantages of renewable

Don’t provide much energy
Not efficient
Weather dependant

17

Biofuels

Made from plants and waste
Can not respond to immediate energy demands
Cost lots
Increases methane and carbon dioxide emissions
Reliable because crops grow quickly

18

Wind power

Initial costs are high but minimal to run
No pollution
Lots of them are needed to produce lots of power
Spoil the view
Noisy
Only work when wind so can’t always supply to high demand

19

Solar cells

No pollution
Initial costs are high but minimal to run
Generate small scale electricity
Most suitable for sunny countries
No power made at night
Can’t increase production when there is extra demand

20

Hydro-electricity

No pollution
Big impact on environment due to flooding possible loss of housings or habitats
Immediately respond to increased electricity demand
Initial costs are high but minimal running cost
Generally reliable

21

Tidal barrages

No pollution
Effect boat access
Can spoil view
Alter wildlife
Reliable
Don’t work when water levels are equal both sides
Initial costs are high but minimal running costs
No fuel costs