Current and Charge
0.0 / 5
- Created by: ColourPages
- Created on: 05-04-17 18:27
Electric Current
- The rate of flow of charge
- Symbol I
- Measured in amperes ( A )
- Normally a flow of electrons in metals
- Or flow of ions in electrolytes
1 of 24
Amperes
- Base SI unit of electric current
- Symbol (A)
- Defined as the current flowing in two parallel wires in a vacuum 1m apart such that there is an attractive force of 2 x 10 -7 N per metre length of wire between them
2 of 24
Positive
One type of electric charge, attract negative repel other positives
3 of 24
Negative
A type of electric charge such that it repels other negative charge and attracts positive charge.
4 of 24
Coulomb (C)
- The derived SI unit of electric charge.
- 1 coulomb of electric charge passes a point each second when there is a current of one amp
- 1 coulomb = 1 amp x second
5 of 24
Electric Charge
- Physical property (symbol of q or Q)
- Positive or negative
- Measured in coulombs or as a relative charge
6 of 24
Ion
- An atom that has either lost or gained electrons
- Has a net charge
7 of 24
Relative Charge
- A simplified measurement of the electric charge of a particle or object
- Measured in multiples of the elementary charge (q or e)
8 of 24
Quantise
- The availabilty of some quantities only in certain discrete values
- Examples are elementary charge
9 of 24
Conventional Current
- A model used to describe electric current in a circuit
- Travels from positive to negative
10 of 24
Free Electrons
- An electron in a metal that is not bound by an atom and is free to move.
- AKA a delocalised electron
11 of 24
Electrolytes
- A liquid containing ions that are free to move and so conduct electricity
12 of 24
Ionic Solutions
- An ionic compound dissolved in a liquid
- This forms an electrolyte
13 of 24
Cations
A positively charged ion attracted to a cathode. (Which are negatively charged)
14 of 24
Anion
A negatively charged ion attracted to an anode.
15 of 24
Cathode and Anode
Cathode - a negatively charged electrode
Anode - a positively charged electrode
16 of 24
Ammeter
- A device used to measure electric current
- Placed in series in a circuit and ideally has zero resistance
17 of 24
Resistance
- Property of a component calculated by divided the potential difference across it by the current in it.
- Symbol R, unit ohm
18 of 24
Potential Difference
- Defined as the energy transferred from electrical to other forms per unit charge
19 of 24
Conservation of charge
- States electric charge cannot be created or destroyed
- Total charge in any interaction is the same before and after said interaction
20 of 24
Kirchhoff's First Law
- At any point at a circuit the current entering is the same as the current leaving
- Electrical charge is conserved
21 of 24
Number Density
- The number of free electrons per cubic metre of material.
- Symbol n, unit 1/m-3
22 of 24
Semi-conductors
- A material with a lower number density than a typical conductor.
- Number density typically of order 10 to the 17 1/m3
23 of 24
Mean Drift Velocity
- The average velocity of electrons as they move through a wire
- Symbol v, units metres per second
24 of 24
Related discussions on The Student Room
- How exactly does step up/down transformers work? »
- Physics homework help »
- Edexcel A Level Physics Paper 1: Advanced Physics I 9PH0 01 - 24 May 2023 [Exam Chat] »
- Fun top secret info, Spread to your friends/try the first three »
- AQA A Level Physics Paper 2 7408/2 - 10 Jun 2022 [Exam Chat] »
- How to find energy suppliers (first time renting) »
- Edexcel A Level Physics Paper 3: 9PH0 03 - 15th June 2023 [Exam Chat] »
- Charge, Voltage, Current »
- A level physics help »
- edexcel physics alevel question »
Similar Physics resources:
3.0 / 5 based on 2 ratings
1.0 / 5 based on 2 ratings
0.0 / 5
4.5 / 5 based on 2 ratings
0.0 / 5
3.0 / 5 based on 1 rating
2.0 / 5 based on 1 rating
0.0 / 5
Comments
No comments have yet been made