energy stores

Question 1

name all the energy stores

Answer 1

. kinetic store
. chemical
. elastic potential
.nuclear store
. gravitational potential
. thermal energy store
.magnetic store
. electrostatic

Question 2

Name four different pathways

Answer 2

mechanic= moving objects
heating=temperature
radiation= wave or sound
electricity= electric current

Question 3

formula for kinetic

Answer 3

kinetic= 1/2 x mass(kg) x speed 2(m/s)

Question 4

formula for G.P.E

Answer 4

G.P.E= mass(kg) x gravitational field strength(N/kg) x height(m)

Question 5

formula for power

Answer 5

energy transferred(j) / time (s)

Question 6

work done

Answer 6

work done = force *distance

Question 7

specific heat capacity

Answer 7

the specific heat capacity of a substance is the amount of energy required to raise the temperature

Question 8

formula for specific heat capacity

Answer 8

change in thermal energy= mass x specific heat capacity x temperature

Question 9

law of conservation of energy

Answer 9

energy can be transferred usefully, stored or dissipated but it cannot be created or destroyed

Question 10

how to reduce unwanted energy transfers by reducing friction?

Answer 10

. use a lubricant

. remove the air particles from around the pendulum

Question 11

power

Answer 11

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

Question 12

power formula for energy transferred

Answer 12

power= energy transferred / time

Question 13

power formula for work done

Answer 13

power= work done / time

Question 14

formula for efficiency

Answer 14

efficiency = useful power output / total power input

Question 15

thermal conductivity

Answer 15

the higher the thermal conductivity of a material, the higher the rate of energy transfer by conduction across that material.

Question 16

how to reduce thermal energy transfer from a house?

Answer 16

. construct the building using materials with a low thermal conductivity.

. build the house with thick walls as this also reduces the rate of thermal energy transfer