Electrical Power

Question 1

What is power?

Answer 1

Rate at which work is done or energy is transferred

Question 2

What are the units for power?

Answer 2

Joules per second (Js-1) or more commonly WATTS (W)

Question 3

What is the formula for power??

Answer 3

P=IV

P= power
I= current
V= voltage

Question 4

Kilowatt-hours…..what are they?

Answer 4

the unit of measurement for the amount of energy used by a household

Question 5

What does AC stand for?

Answer 5

Alternating Current

Question 6

What does DC stand for?

Answer 6

Direct current

Question 7

What is the difference between AC and DC

Answer 7

DC: movement of electrical charge in ONE DIRECTION
- Inefficient
-has a large energy loss

AC: electric charge oscillates (moves back and forth) to transfer energy
- very efficient
- not much energy loss

Question 8

What do household electricity usually show?

Answer 8

energy used = Power x time
(unit = Kwh (killowatt per hour))

Question 9

Why is there some energy loss in electrical stuff?

Answer 9

Transferring electric charge to make electrical energy can emit unwanted heat or light energy

Question 10

What is Direct Current (DC)?

Answer 10

Movement of electric charge in 1 direction

Question 11

What is Alternating Current (AC)?

Answer 11

Movement of electric charge through periodic oscillation of charge

Question 12

Is AC or DC more efficient and why?

Answer 12

AC is more efficient because it has less energy loss as its charge doesn’t need to travel far