Energy

Question 1

Name all 8 Energy?

Answer 1

> Thermal, Kinetic, Gravitational, Magnetic,
Electrostatic, Nuclear, Elastic potential, Chemical.

Question 2

How is energy trasnfered?

Answer 2

Mechanically,Electrically,or by heating/radiation

Question 3

What is a closed system?

Answer 3

Closed systems are systems where neither matter nor energy can enter/leave.

Question 4

What happens when a system changes?

Answer 4

Energy is transferred into or away from the system, between different objects in the system.

Question 5

What is Work Done?

Answer 5

Whenever energy is transferred from one store to another.

Question 6

What is the formula for Work Done?

Answer 6

Work Done (J) = Force (N) x Distance (m)

Question 7

What is the formula for Kinetic Energy

Answer 7

Ek = 0.5 X m x V^2

Question 8

What is G.P.E?

Answer 8

The energy stored in an object due to its position above the Earth’s surface, this is due to the force of gravity acting on an object.

Question 9

What is the formula for G.P.E?

Answer 9

Ep = M X g X h

Question 10

What is E.P.E?

Answer 10

When we stretch a spring were applying force to change the length of the spring.

Question 11

What is the formula for E.P.E?

Answer 11

Ee = 0.5 X k X e^2

Question 12

What is the rule of Energy?

Answer 12

Energy can be transferred useful, stored or dissipated, but can never be created or destroyed.

Question 13

Formula for Power?

Answer 13

Power = Energy transferred/Work Done
————————————————
Time (s)

Question 14

What is Conduction?

Answer 14

The process where vibrating particles transfer energy to neighboruing particles.

Question 15

What is Convection?

Answer 15

> Where energetic particles move away from hotter to cooler regions.

Question 16

Explain how to reduce energy loss?

Answer 16

> Thick walls- reduce heat loss by conduction (Low thermal conductivity).
Cavity walls- reduce conduction
Windows - Single/double glazing
Double glazing is 2 layers of glass so reduced conduction.
Single glazing heat is lost easily by conduction.

Question 17

What is the formulae for Efficiency?

Answer 17

Useful output energy transfer
Efficiency= ———————————————-
Total input energy transfer

Question 18

Pros and Cons of wind turbines?

Answer 18

Pros:
>Renewable
Cons:
>Takes a lot of space
>Expensive
>Dependent on strength of the wind
>If wind is too strong it can break.

Question 19

Pros and Cons of Solar Power?

Answer 19

Pros:
>Low running costs
>Doesn’t produce any harmful pollutants.

Cons:
>Dependent on weather
>High upfront cost
>Produces pollutants while making them
>No way to increase demand of supply
>Takes up a lot of space.

Question 20

Pros and Cons of geothermal

Answer 20

Pros:
>Renewable energy
>Doesn’t release any pollutants

Cons:
>Expensive
>Only works in volcanic regions

Question 21

Pros and Cons of Biofuels?

Answer 21

Pros:
>Cheap to make
>Renewable
>Easy to transport

Cons:
>Need somewhere to grow all plants
>Damages environment for space
>Requires energy for harvesting and transport so more CO2 released.

Question 22

Pros and Cons of Hydroelectric?

Answer 22

Pros:
>Provides an immediate response to an increased demand for electricity.
>Reliable except in droughts
>No fuel costs and running costs
>Useful to generate electricity on a small scale.

Cons:
>Big impact on environment
>Loss of habitat
>Rotting vegetation releases methane
>High initial costs

Question 23

Pros and Cons of Wave Power?

Answer 23

Pros:
>No pollution
>No fuel costs
>No running costs
>Can be useful on small islands

Cons:
>Disturbs the sea bed and habitats
>Spoils the view and hazardous to boats
>Fairly unreliable waves tend to die when wind drops
>Costs are high

Question 24

Pros and Cons of Tidal barrages?

Answer 24

Pros:
>No pollution
>Reliable
>No fuel costs
>No running Costs
>Produces significant amount of energy

Cons:
Prevents access of boats spoils the view
>Don’t work when water levels are same on both sides
>High Costs

Question 25

Explain a method to carry out Specific Heat Capacity?

Answer 25

1)Place the immersion heater into the central hole at the top of the block.
2)Place the thermometer into the smaller hole and put a couple of drops of oil into the hole to make sure the thermometer is surrounded by hot material.
3)Fully insulate the block by wrapping it loosely with cotton wool.
4)Record the temperature of the block.
5)Connect the heater to the power supply and turn it off after ten minutes.
6)After ten minutes the temperature will still rise even though the heater has been turned off and then it will begin to cool. Record the highest temperature that it reaches and calculate the temperature rise during the experiment.