P1

Question 1

What are the eight energy stores?

Answer 1

Kinetic,
thermal,
chemical,
elastic potential
gravitational potential
electrostatic
magnetic
nuclear

Question 2

What is the conservation of energy?

Answer 2

Energy can never be created or destroyed, just transferred from one form to another.

Question 3

What is specific heat capacity?

Answer 3

The amount of energy needed to raise the temperature of 1 kg of a substance by one degrees Celsius

Question 4

What is the definition of power?

Answer 4

The rate at which energy is transferred or the rate at which work is done

Question 5

What is the unit of Power?

Answer 5

Watt(w)

Question 6

What is a renewable energy resource?

Answer 6

An energy source, which can be replenished as it is being used up?

Question 7

what is Kinetic energy

Answer 7

the energy stored in moving objects
stationary objects have no KE

Question 8

how do we calculate KE

Answer 8

0.5xmassxspeed

Question 9

what is elastic potential energy

Answer 9

the energy that is stored in a stretched spring

Question 10

how is extension linked to force appilied

Answer 10

extension is directly proportional to force applied until the limit of proportionality

Question 11

what is meant by gravitational potential energy

Answer 11

energy stored in an object due to its position above the earths surface
this is due to the force of gravity acting on an object

Question 12

how do we calculate gravitational potential energy

Answer 12

mass x
gravitational field strength x
height

Question 13

what is thermal energy

Answer 13

the energy stored in an object due to its temperature

Question 14

what is a system

Answer 14

an object or group of objects

Question 15

what is a closed system

Answer 15

no energy can enter or leave

Question 16

what is the energy transfer like in a pendulum

Answer 16

-at the max height the mass has the most amount of GPE
-as the pendulum swings the GPE is transferred to KE
-the mass has the maximum amount of KE at the bottom of the swing
-As the mass swings back up the KE is transferred to GPE again

Question 17

what does friction do as the pendulum swings

Answer 17

-friction causes energy to be transferred to thermal energy
-the fixed point and the air around the pendulum gradually get warmer
-thermal energy store is less useful and therefore energy is getting dissipated (wasted)
-the pendulum now swings with less energy and gradually stops

Question 18

how do we reduce friction in a pendulum

Answer 18

-reduce air particles
-use lubricants

Question 19

what happens to the energy stores during a bungee jump

Answer 19

-at the start all of the energy in the system is stored in GPE
-as the jumper falls energy is transferred from GPE to KE
-when the bungee rope starts to tighten,KE energy store is at its maximum
-when the rope is fully extended the KE is zero
-at this point all the energy is transferred to EPE
-bungee rope recoils,EPE is transferred to KE
-during the acend KE is transferred to GPE
-at the top of the acend all the energy is GPE

Question 20

why does the bungee jumper never return to their original position

Answer 20

-energy is dissipated as thermal enrgy
-due to friction with air particles
-due to stretching effects with bungee rope

Question 21

what is work done

Answer 21

whenever energy is transferred from one store to another

Question 22

what is mechanical work

Answer 22

using a force to move an object

Question 23

what is electrical work

Answer 23

current transferring energy

Question 24

how do we calculate work done(j)

Answer 24

force x distance

Question 25

what is the equation for power involving work done

Answer 25

work done/time

Question 26

what is the equation for power involving energy transferred

Answer 26

energy transferred/time

Question 27

what does efficiency tell us

Answer 27

tells us the fraction of the energy what we put into an appliance is transferred into useful energy

Question 28

what is the equation for efficiency

Answer 28

useful power output/
total power input

Question 29

what is the positives of using nuclear power to generate energy

Answer 29

-releases no carbon dioxide,does not contribute to climate change
-extremely reliable

Question 30

how can we reduce loss of heat from buildings

Answer 30

-fill cavities with insulating materials with low thermal conductivity
-double glaze windows
-loft insulation with low thermal conductivity

Question 31

what is the negatives of using nuclear power to generate energy

Answer 31

-contain highly dangerous radioactive materials,if released by accident it would be potentially disastrous
-decommissioning takes many years and is very expensive

Question 32

why is the total positive charge in every atom of an element always the same

Answer 32

-positive charge is carried by protons
-every atom of the same element carry the same number of protons

Question 33

how is heat lost through the walls of buildings

Answer 33

-energy is transferred through conduction