Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

A Level Physics > Module 4: Chapter 9 - Energy, Power, and Resistance > Flashcards

Module 4: Chapter 9 - Energy, Power, and Resistance Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What is the difference between a cell and a battery?

A

A cell is a single cell whereas a battery is multiple cells connected in series

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

What is a cell?

A

An electrical component that provides the “push” for electrons in a circuit

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

What is an ammeter?

A

An electrical component that is used to measure current

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

What is a voltmeter?

A

An electrical component used to measure potential difference

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

What is a lamp?

A

An electrical component that emits light when current passes through it

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

What is an LDR?

A

Light Dependent Resistor

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

What is a fuse?

A

An electrical component that melts and breaks the circuit if the current is too high

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

What is a resistor?

A

An electrical component that limits the current in a circuit

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

What is an LED?

A

An electrical component that emits light when a current passes through it

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

What is a switch?

A

An electrical component that enables current in a circuit to be switched on or off

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

What is a Thermistor?

A

Temperature Dependent Resistor

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

What is a variable resistor?

A

An electrical component that allows current to be varied

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

What is the circuit symbol for a cell?

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

What is the circuit symbol for an ammeter?

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

What is the circuit symbol for a voltmeter?

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

What is the circuit symbol for a lamp?

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

What is the circuit symbol for an LDR?

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

What is the circuit symbol for a fuse?

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

What is the circuit symbol for a resistor?

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

What is the circuit symbol for an LED?

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

What is the circuit symbol for an open switch?

A
22
Q

What is the circuit symbol for a closed switch?

A
23
Q

What is the circuit symbol for a thermistor?

A
24
Q

What is the circuit symbol for a variable resistor?

A
25
Q

What is a diode?

A

A diode is an electrical component that only allows current to flow in 1 direction

26
Q

What is the circuit symbol for a diode?

A
27
Q

What is a capacitor?

A

A component that stores charge, consists of two plates separated by an insulator (dielectric)

28
Q

What is the circuit symbol for a capacitor?

A
29
Q

What are the rules for drawing circuit diagrams?

A
  • Only use official circuit symbols
  • Do not leave any gaps between the wires
  • Use straight drawn lines for wires
30
Q

Which terminal on a cell symbol is positive and which is negative?

A

The longer terminal is positive and the shorter terminal is negative

31
Q

What is potential difference?

A

A measure of the electrical energy transferred per unit charge

32
Q

What si the equation for potential difference?

A

Potential difference = work done / charge
P = W/Q

33
Q

How is a voltmeter connected in a circuit?

A

In parallel

34
Q

Why is a voltmeter connected in parallel with a circuit?

A

Voltage is a measure of the difference in energy between 2 points (energy transferred to device between 2 points). Therefore it must be connected in parallel to be used to measure the difference in potential across a device

35
Q

What should be the resistance of a theoretically perfect voltmeter and why?

A

Infinite resistance so that no current can pass through the voltmeter, however this is not realistically possible so most voltmeters have a resistance of several million ohms

36
Q

What is a volt?

A

The unit of potential difference, it is defined as the energy transferred per coulomb of charge as charges mobe between 2 points in a circuit

37
Q

What is Electromotive force (EMF)?

A

The energy transferred to the charge carriers by the cell/battery

38
Q

What is the difference between EMF and PD?

A

EMD is the energy transferred to charge carriers (a transfer of energy from the cell/battery to the charge carriers), whereas PD is the energy transferred by charge carriers (a transfer of energy from the charge carriers to the component)

39
Q

What is the equation for EMF?

A

EMF = work done / charge
ε = W/Q

40
Q

What is resistance?

A

The resistance of a component is the ratio between the potential difference across a component and the current flowing through it (the opposition to the flow of current)

41
Q

What is the equation for resistance?

A

Resistance = PD/current
R = V/I

42
Q

What is the unit for resistance?

A

Ohms (Ω)

43
Q

What is an ohm in base units?

A

Ω = kg m² A⁻² S⁻³

44
Q

What is ohms law?

A

For a metallic conductor at a constant temperature the potential difference across the conductor is directly proprotional to the current through the conductor

45
Q

What is the equation for ohms law?

A

V = IR

46
Q

What is the gradient on a V-I graph

A

The resistance

47
Q

What does a V-I graph for a resistor which follows ohm’s law look like?

A
48
Q

Why does current decrease in a wire over time?

A

Over time, the electrons flowing through the circuit will collide with the metal ions in the wire, transferring energy to the ions and causing them to vibrate with a greater amplitude about their mean positions. This causes the frequency of collisions between the charge carrier (electrons) and metal ions to increase. Therefore the resistance of the wire increases, causing the current to decrease

49
Q

What is used to measure PD?

A

A voltmeter

50
Q

What is the unit of EMF?

A

volt

51
Q

An electron with initial kinetic energy of 100eV and initial speed 5.9x10^6 ms^-1 is accelerated through a potential difference of 250V, what is the final speed?

A

1.1x10^7 ms^-1

A Level Physics (29 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions