efficiency

Question 1

what is useful energy

Answer 1

energy transfered to where it is wanted in the way it is wanted

Question 2

what is wasted energy

Answer 2

energy that is not usefully transfered

Question 3

t or f when enegery is transfered we can make 0 wasted energy

Answer 3

false if any energy is transfered some energy is always wasted

Question 4

input energy=

Answer 4

useful energy + wasted energy

Question 5

what is efficieny

Answer 5

a measure of how much of the energy we put in ends up in useful energy stores

Question 6

how do we calculate efficiency

Answer 6

efficency =useful output energy/total input energy

Question 7

what is the units for efficiency

Answer 7

has no units because the joules cancle out

may sometimes be percent

Question 8

effiency should always be between ___

Answer 8

1 and 0

Question 9

what does it mean if efficeny is more than 1

Answer 9

the useful energy out would be more than the total input which cannot be possible because the law of conservation of energy means energy can’t be created or destroyed

Question 10

what can we do to our ans to turn it into a %

Answer 10

x 100

Question 11

what are the 2 main scources where most energy is wasted

Answer 11

work done to over come friction(moving parts rubbing)

unwanted heat transferes (heat dissipating)

Question 12

how can we reduce the 2 main wasted energy scources

Answer 12

lubricating moving parts

adding insulation to reduce heat loss

Question 13

why do some objects feel hot

Answer 13

the atoms are moving faster on average even though the atoms are not hot

Question 14

what is the difference between efficeny and power

Answer 14

Power is how fast energy is transferred, while efficiency is how much of that energy is usefully transferred.