Measuring Current
Science: KS3, topic 3.4.4
Measuring Current
Current is the flow of electrical charge. We are able to measure current using an ammeter.
Ammeters
- An ammeter is the device used to measure current.
- Current is measured in amps, which is short for amperes.
- The symbol we used for amps is an ‘A’.
Multimeter and series
- Another device that is able to measure current is called a multimeter.
- Ammeters are added to the circuit in series.
Flow direction
- Electrons flow from the negative terminal to the positive terminal.
- In 1750, the American scientist Benjamin Franklin was one scientist.
Franklin's wrong theory
- Franklin wrongly believed current moved from the positive to the negative.
- We now know Franklin's theory was wrong.
- However, we still name Franklin's theory ‘conventional current’.
Test yourself on Measuring Current
In which way do electrons flow?
Franklin's theory says conventional current flows from positive to negative. Electrons actually flow from negative to positive. How do these two directions compare?
Which of these are true of current?