Electricity Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is current

A

A flow of electrical energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Increasing the flow of current has the effect of what

A

Faster, brighter and warmer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is electric current measured in

A

Amperes or amps (A)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do you measure current

A

Using an ammeter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

When testing different materials what does a conductor allow

A

Electric current to flow through it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When testing materials what doesn’t an insulator allow

A

Electric current to flow through it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

For an electrical current to flow what do we need

A

A complete circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the flow of current in a series circuit

A

The same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

In a simple series circuit where is everything connected

A

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)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Current in a series circuit summary:

Talk about the current as different positions in the circuit

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Current in a series circuit summary:

What is current not used up by

A

By the components in the circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Current in a series circuit summary:

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

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

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

A

The same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Current in a series circuit summary:

Tell me about current flow in a series circuit

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Current in a series circuit summary:

Tell me about conventional current

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Current in a series circuit summary:

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

A

It has the same value

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Current in a series circuit summary:

Tell me about electron flow

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Current in a series circuit summary:

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

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is voltage

A

The amount of push

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do we measure voltage across a resistor or a bulb

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are components

A

Resistors or bulbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

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….

A

Flow

Push

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

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……..

A

Same

Decreased

24
Q

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

A

Voltage
Added
Equal

25
Q

What is a parallel circuit

A

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

26
Q

How many oaths are there around a parallel circuit

A

More than 1

27
Q

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

A

The same

28
Q

What does the current get used by in a parallel circuit

A

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

29
Q

Give a summary of parallel circuits

A

The sum of the current in the branches is equal to the current that leaves the cell

The voltage across each branch is equal

30
Q

Electricity and magnetism full summary:

What is the flow of current

A

The movement of electrical charge, usually electrons

31
Q

Electricity and magnetism full summary:

Where do electrons move from and where to

A

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

32
Q

Electricity and magnetism full summary:

What is conventional current flow like

A

It’s from positive to negative

33
Q

Electricity and magnetism full summary:

In a series circuit what does the current split into

A

Continuous loops

34
Q

Electricity and magnetism full summary:

In a parallel circuit what does the current split into

A

Into separate branches

35
Q

Electricity and magnetism full summary:

What is a short circuit like for electrons to flow

A

It’s a very easy route for electrons to flow

36
Q

Electricity and magnetism full summary:

Explain the resistance to current of an insulator and a conductor

A

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

37
Q

Electricity and magnetism full summary:

What does an ammeter measure current in and what does a voltmeter measure PD and EMF in

A

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

38
Q

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

A

An insulator and conductor

39
Q

An ammeter measures what and must be placed where

A

It measures current and must be placed in a circuit

40
Q

What does a voltmeter measure and where must it be placed

A

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

41
Q

What units do ammeters and voltmeters measure in

A

Ammeter - amps

Voltmeter - volts

42
Q

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…….

A
Variable
Diode
One direction 
Electrons
Higher
Less
Current
On
Output
One
Output
43
Q

Electrons moving round a circuit constitute what

A

A current

44
Q

What do electrons carry

A

Energy in the form of charge

45
Q

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

A

The larger the current

46
Q

If Q=It

What does I equal

A

I = Q/t

47
Q

In the equation Q=It

What does the Q, I, t stand for

A

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

48
Q

Resistor networks:

In series…..

A

Just add them together

49
Q

Resistor networks:

In parallel……

A

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

50
Q

1/Rparallel = what

A

1/R1 + 1/R2

Could write as….

  1                      1                 1 ---------      =  -----     +   ----- Rparallel             R1               R2
51
Q

How do we study the effect in voltage across a resistor

A

This is done using the 2 meter method

52
Q

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

A

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

53
Q

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

A

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

54
Q

A component that gives a straight line graph is called what

A

An ohmic conductor

55
Q

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

A

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

56
Q

What is the definition of Ohm’s law

A

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

57
Q

Put this equation in to words

V=IR

A

Voltage = current X resistance