power

Question 1

what is power

Answer 1

power is the rate of energy transfer

Question 2

a device that is more powerful transferes energy ____

Answer 2

quicker

Question 3

how do we calculate power

Answer 3

P=E/t

P=W/t

Question 4

what does the E stand for in the equation and units

Answer 4

energy transfered

joules/J

Question 5

what does the t stand for and unit

Answer 5

time
seconds/s

Question 6

1 watt=

Answer 6

1 joule per second

Question 7

1 joule per second=

Answer 7

1 watt

Question 8

energy transfer=

Answer 8

work done

Question 9

what does the W stand for and units

Answer 9

work done
joules/J

Question 10

which uses more energy ,walking up the stairs or running up the stairs

Answer 10

If the question is about going up stairs or a hill, it is testing gravitational potential energy, so the energy used is E=mgh. Since the mass and height are the same, walking and running use the same total energy, but running uses more power because it is done faster. However, if the situation is on a flat path, there is no gain in gravitational potential energy, so the energy depends on kinetic energy instead. Running is faster, so it has greater kinetic energy and therefore uses more energy and more power than walking.