Current Electricity

Question 1

what happens when insulated materials are rubbed together?

Answer 1

the material becomes charged (either negatively or positively)

Question 2

What is transferred when the objects become charged?

Answer 2

either:

• The material becomes negatively charged (gains electrons)
• The material becomes positively charged (looses electrons)

Question 3

what happens to oppositely charged materials

Answer 3

they attract

Question 4

what happens to materials with the same charge

Answer 4

they repel

Question 5

What does an ammeter measure?

Answer 5

the current

Question 6

what does a voltmeter measure?

Answer 6

Potential difference (volts)

Question 7

what does Ohm’s law state?

Answer 7

The current through a resistor at constant temperature is directly proportionate to the potential difference across the resistor

Question 8

reversing the current through a component also reverses what?

Answer 8

the voltage

Question 9

what happens to the resistance of a filament bulb when the temperature of it increases?

Answer 9

it increases.

Question 10

what is the resistance like of a diode with a forward current?

Answer 10

low resistance

Question 11

what is the resistance like of a diode with a reverse current?

Answer 11

high resistance.

Question 12

what happens to a thermo resistor if the temperature of it increases

Answer 12

it’s resistance decreases

Question 13

what does LDR stand for?

Answer 13

Light Dependent resistor

Question 14

resistance of the LDR changes how if the light intensity on it increase?

Answer 14

resistance decreases

Question 15

in a series circuit how is the current distributed to each component?

Answer 15

each component has equal current

Question 16

in a series circuit how is the potential difference distributed?

Answer 16

the potential difference is shared between all components.

Question 17

the total potential difference of each cell in a series circuit = what?

Answer 17

the total potential difference (providing that all cells are acting in the same direction)

Question 18

how do we work out the total resistance of all components in a series circuit?

Answer 18

we add the resistance of each component together.

Question 19

The total current through a parallel circuit is

Answer 19

the sum of the currents through the separate components

Question 20

in a parallel circuit the bigger the resistance of a component the

Answer 20

smaller the current is.

Question 21

in a parallel circuit the potential difference is

Answer 21

the same across each circuit