elec. comp

Question 1

whats the function of a dry cell

Answer 1

drives elec. charges arnd an electric circuit

Question 2

whats the function of a bulb

Answer 2

produces light using electricity

Question 3

whats the energy conv in a bulb (e->e+e)

Answer 3

elec. energy -> light energy + heat energy

Question 4

whats the energy conversion in a dry cell (battery)?

Answer 4

chemical poten. energy -> elec. energy

Question 5

whats the function of a switch?

Answer 5

opens or closes a circuit

Question 6

whats the function of an ammeter?

Answer 6

measures the amt of current flowing through an elec. circuit / component

Question 7

what arrangement should an ammeter be connected in?

Answer 7

series

Question 8

whats the purpose of a fixed resistor?

Answer 8

to restrict or limit the flow of an electric current

Question 9

whats the purpose of a variable resistor?

Answer 9

to vary the amt of current flowing ina circuit (by changing the resistance value)

Question 10

whats the SI unit for current?

Answer 10

ampere (A)

Question 11

whats the SI unit for potential difference?

Answer 11

voltage (V)

Question 12

whats the SI unit for resistance?

Answer 12

ohms (Ω)

Question 13

whats potential difference?

Answer 13

the amt of energy needed to move one unit charge from one place to another

Question 14

what’s resistance?

Answer 14

a measure of how much an electrical component opposes the flow of electric charges

Question 15

whats the function of a fuse?

Answer 15

a safety device that prevents excessive current flow

Question 16

whats the function of a circ. breaker?

Answer 16

to cut off electrical supply in a circuit when the current flowing through is too large

Question 17

whats the formula for finding power? (?=?/?)

Answer 17

power=energy/time (eg: watt=joule/second)

Question 18

whats 19W in kW?

Answer 18

0.019kW

Question 19

what does it mean to say that the LED bulb has a power rating of 19W?