Electricity

Question 1

What is current

Answer 1

A flow of electrical energy

Question 2

Increasing the flow of current has the effect of what

Answer 2

Faster, brighter and warmer

Question 3

What is electric current measured in

Answer 3

Amperes or amps (A)

Question 4

How do you measure current

Answer 4

Using an ammeter

Question 5

When testing different materials what does a conductor allow

Answer 5

Electric current to flow through it

Question 6

When testing materials what doesn’t an insulator allow

Answer 6

Electric current to flow through it

Question 7

For an electrical current to flow what do we need

Answer 7

A complete circuit

Question 8

What is the flow of current in a series circuit

Answer 8

The same

Question 9

In a simple series circuit where is everything connected

Answer 9

In one loop across the terminals of the battery. So there aren’t any points where the current can spilt or join (these are called junctions)

Question 10

Current in a series circuit summary:

Talk about the current as different positions in the circuit

Answer 10

The current at different positions in the circuit, before and after the resistor, was the same. Current is not used up by the components in the circuit

Question 11

Current in a series circuit summary:

What is current not used up by

Answer 11

By the components in the circuit

Question 12

Current in a series circuit summary:

What happened when you increased the number of components in the circuit

Answer 12

It decreased the current. The current at all points in a series circuit is the SAME

Question 13

What is the current like at all points in a series circuit

Answer 13

The same

Question 14

Current in a series circuit summary:

Tell me about current flow in a series circuit

Answer 14

When we talk about current flowing, we say that current flows out of the cell and back into the negative terminal

Question 15

Current in a series circuit summary:

Tell me about conventional current

Answer 15

Conventional current flows from the positive pole to the negative pole. It has the same value at any point in the circuit

Question 16

Current in a series circuit summary:

What is the value of conventional current at any point in the circuit

Answer 16

It has the same value

Question 17

Current in a series circuit summary:

Tell me about electron flow

Answer 17

The electrons flow from the negative side of the battery to the positive side. These are the particles that are actually moving through the conductor

Question 18

Current in a series circuit summary:

What is the difference between the electrons in a circuit flow compared to conventional current

Answer 18

The electrons in a circuit flow from the negative pole to positive pole. The opposite direction to conventional current

Question 19

What is voltage

Answer 19

The amount of push

Question 20

How do we measure voltage across a resistor or a bulb

Answer 20

Voltage is measured by connecting the voltmeter across (or in PARALLEL with) the COMPONENT. Voltage is measured in volts and the symbol for this is V

Question 21

What are components

Answer 21

Resistors or bulbs

Question 22

Fill in the blanks:
Remember we are still talking about series circuits!!
The current is the….of energy around the circuit. The voltage is the amount of….

Answer 22

Flow

Push

Question 23

Fill in the blanks:
REMEMBER WE ARE TALKING ABOUT SERIES CIRCUITS.
when two components were put into circuit 2, the voltage of the supply was the…..as circuit one. However, the voltage across R1……..

Answer 23

Same

Decreased

Question 24

Fill in the blanks:
REMEMBER we are still talking about series circuits
The………across both components in circuit 2……to be……to the supply voltage

Answer 24

Voltage
Added
Equal

Question 25

What is a parallel circuit

Answer 25

A parallel circuit is one that contains a point (a junction) where the current can split (point a) or join (point b) This means there is more than one path around the circuit

Question 26

How many oaths are there around a parallel circuit

Answer 26

More than 1

Question 27

For a parallel circuit, the current that leaves the cell is what in comparison to the current that returns to the cell

Answer 27

The same

Question 28

What does the current get used by in a parallel circuit

Answer 28

The current does NOT get used by the circuit, just the energy that the electrons are carrying

Question 29

Give a summary of parallel circuits

Answer 29

The sum of the current in the branches is equal to the current that leaves the cell The voltage across each branch is equal

Question 30

Electricity and magnetism full summary: | What is the flow of current

Answer 30

The movement of electrical charge, usually electrons

Question 31

Electricity and magnetism full summary: | Where do electrons move from and where to

Answer 31

Electrons move from the negative terminal of a cell to the positive terminal of a cell

Question 32

Electricity and magnetism full summary: | What is conventional current flow like

Answer 32

It's from positive to negative

Question 33

Electricity and magnetism full summary: | In a series circuit what does the current split into

Answer 33

Continuous loops

Question 34

Electricity and magnetism full summary: | In a parallel circuit what does the current split into

Answer 34

Into separate branches

Question 35

Electricity and magnetism full summary: | What is a short circuit like for electrons to flow

Answer 35

It's a very easy route for electrons to flow

Question 36

Electricity and magnetism full summary: | Explain the resistance to current of an insulator and a conductor

Answer 36

An insulator has a very high resistance to current and a conductor has a low resistance to current

Question 37

Electricity and magnetism full summary: | What does an ammeter measure current in and what does a voltmeter measure PD and EMF in

Answer 37

An ammeter measures current in amps and a voltmeter measures PD and EMF in volts

Question 38

Current flows easily through a short circuit but what does it not flow easily through

Answer 38

An insulator and conductor

Question 39

An ammeter measures what and must be placed where

Answer 39

It measures current and must be placed in a circuit

Question 40

What does a voltmeter measure and where must it be placed

Answer 40

A voltmeter measures PD and EMF in volts and must be placed in the component of a circuit

Question 41

What units do ammeters and voltmeters measure in

Answer 41

Ammeter - amps | Voltmeter - volts

Question 42

Electricity and magnetism 2: Fill in the blanks; In a rheostat the resistance can be...... A.....will allow current to flow in................ When light shines on a LDR many........are released. The........the resistance of a wire, the.....the....... In an AND gate both switches must be....to get an....... In an OR gate only.....input must be on to get an.......

Answer 42

``` Variable Diode One direction Electrons Higher Less Current On Output One Output ```

Question 43

Electrons moving round a circuit constitute what

Answer 43

A current

Question 44

What do electrons carry

Answer 44

Energy in the form of charge

Question 45

In an electron, the faster the flowing charge, the what

Answer 45

The larger the current

Question 46

If Q=It | What does I equal

Answer 46

I = Q/t

Question 47

In the equation Q=It | What does the Q, I, t stand for

Answer 47

Q is the charge measured in coulombs, C. I is the current flowing, ampères or amps, A. t is time in seconds/s

Question 48

Resistor networks: | In series.....

Answer 48

Just add them together

Question 49

Resistor networks: | In parallel......

Answer 49

Resistors in parallel create lower resistance than when the resistors are connected in series

Question 50

1/Rparallel = what

Answer 50

1/R1 + 1/R2 Could write as.... 1 1 1 --------- = ----- + ----- Rparallel R1 R2

Question 51

How do we study the effect in voltage across a resistor

Answer 51

This is done using the 2 meter method

Question 52

If you have a graph showing voltage and current which has the results of a straight line through the origin what does it mean

Answer 52

This means that voltage is directly proportional to current (origin, positive correlation, straight line)

Question 53

Plotting a graph of voltage V against current I, (y against x, or dependent against independent variable) gives a slope gradient of what REMEMBER THE GRAPH IS ABOUT CURRENT AND VOLTAGE

Answer 53

R. The steeper the slope the greater the resistance, the less steep the slope the smaller the resistance

Question 54

A component that gives a straight line graph is called what

Answer 54

An ohmic conductor

Question 55

What metals give a straight line graph when measuring voltage and current

Answer 55

Copper wire and most other metals give this shape of graph, unless they change temperature

Question 56

What is the definition of Ohm's law

Answer 56

The voltage across an ohmic conductor is directly proportional to the current though it at constant temperate

Question 57

Put this equation in to words | V=IR

Answer 57

Voltage = current X resistance