electricity

Question 1

different parts of a circuit?

Answer 1

1. cell 2. diode 3. battery 4. switch 5. bulb 6. ammeter 7. voltmeter 8. LED 9. LDR 10. Fuse 11. resistor 12. thermistor 13. variable resistor

Question 2

Series circuit?

Answer 2

only has one path.

Question 3

parallel circuit?

Answer 3

has more than one path for the current.

Question 4

resistors in a series?

Answer 4

resistances add up so the total resistance is the sum of the individuals (the current remains the same + potential current is shared across the components). Rtotal= R1 + R2

Question 5

resistors in parallel?

Answer 5

total resistance will decrease as more are placed in parallel (potential difference remains the same). Current in the rest of the circuit is the sum of the current through each resistor.

Question 6

Direct Current (DC)?

Answer 6

current flows in 1 direction

Question 7

Alternating Current (AC)?

Answer 7

currently constantly changes direction- supplied to homes

Question 8

Main electricity?

Answer 8

potential difference is 230V and it alternates 50 times per seconds (50Hz) bcs it is AC

Question 9

Earth wire?

Answer 9

yellow and green- connected to metal casing and provides low resistance route to Earth.

Question 10

Neutral wire?

Answer 10

blue- provides return path for current

Question 11

Live wire?

Answer 11

brown- at 230V and is connected to the fuse. Fuse has thin wire that heats, melts, and breaks the circuit if there’s too much current.

Question 12

Cable grip?

Answer 12

holds the cable in place

Question 13

Cable?

Answer 13

contains individual wires

Question 14

Charged object?

Answer 14

creates electric field- force stronger closer to charge and force is experienced around the charge by other charges.

Question 15

Static?

Answer 15

when 2 insulating materials are rubbed together, electrons can be transferred. Like charges- repel, Opposite charges- attract.

Question 16

Resistor graph?

Answer 16

ohmic conductor- current increases in direct proportion to the potential difference.

Question 17

Filament lamp?

Answer 17

current flows through filament lamp + causes metal ions to vibrate- causes temp to rise. Vibrating ions make it harder for current to flow, therefore, resistance increases.

Question 18

diode?

Answer 18

only allows current to flow in direction

Question 19

sensing components- thermistor?

Answer 19

as temperature increases, resistance decreases- used for thermostats to sense temp to turn on/off heating and ventilation

Question 20

sensing components- LDR?

Answer 20

as light intensity increases, resistance decreases- used for streetlights to sense the light levels to turn on/off lighting

Question 21

current?

Answer 21

flow of electrical charge

Question 22

potential difference?

Answer 22

amount of work done by charge

Question 23

ohmic conductor?

Answer 23

conductor that does not change resistance

Question 24

charge?

Answer 24

coulombs (C)

Question 25

current?

Answer 25

amperes (A)

Question 26

potential difference?

Answer 26

Volts (A)

Question 27

resistance?

Answer 27

ohms

Question 28

National Grid?

Answer 28

1. power stations, solar farms, wind farms, wind farms and more produce electricity. 2. step-up transformers increase the potential difference to 230V (and decrease current) to make transmission more efficient. 3. Pylons support the above-ground cables. 4. high voltage cables 5. step-down transformers decrease the potential difference to 230V (and increase current) and make it safer on consumers. 6. Homes and businesses use electricity.

Question 29

electricity equations?

Answer 29

1. QIT
2. PIT
3. PIR (current is squared)
4. EPT
5. EQV
6. VIR