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- State that current is related to the flow of charge.
Current is the flow of charge (electrons) within a circuit.
- State that the current in metals is due to a flow of electrons.
Metallic bonding is the strong attraction between closely packed positive metal ions and a ‘sea’ of delocalised electrons. These delocalised elecetrons can carry charge and move freely through giant the metal structure, thus making metals conductive of electricity.
- Demonstrate understanding that a current is a rate of flow of charge, and recall and use the equation I = Q /t.
Current is the rate of flow of charge in a given point of the circuit.
I = Q ÷ t
where I=current (amperes), Q=charge (coulomb) and t=time (seconds/minutes)
- Use the term potential difference (p.d.) to describe what drives the current between two points in a circuit.
Potential represents how much energy there is to drive a current through the wire and is measured in volts (v).
- Distinguish between the direction of flow of electrons and conventional current.
At first scientists believed that electricity from the positive to the negative terminal of a battery, but then found out that it was actually the other way around- electrons flow from the negative to the positive termianl. In order to not confusing, they called the initial assumption ‘conventional current’.
- Demonstrate understanding that e.m.f. is defined in terms of energy supplied by a source in driving charge round a complete circuit.
Well, learn that definition.
Notes submitted by Lintha
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