Electric current

Question	Answer
Define electric current	Current is defined as 'the rate of flow of charge'.
State the unit of charge and give its symbol.	The unit of charge is the coulomb (symbol: C ).
Give the equation for electric current	Image: current_equation (image/png)
According to this equation, one amp is equivalent to... Image: current_equation__no_text_ (image/png)	One amp is equivalent to one coulomb per second. Image: 1A_1Cs-1 (image/png)
Define the coulomb	One coulomb is the charge transferred when a current of one amp flows for one second.
Re-arrange this equation to make charge the subject. Image: current_equation__no_text_ (image/png)	Image: Q_It (image/png)
The current in a certain wire is 0.35 A. Calculate the charge passing a point in the wire in i) 10 s, ii) 10 min.	Use this equation and don't forget that time must be given in seconds. Answers: i) 3.5 C ii) 210 C Image: Q_It (image/png)
Calculate the average current in a wire tyhrough which a charge of 15 C passes in i) 5 s, ii) 100 s.	Use this equation. Answers: i) 3 A ii) 0.15 A Image: current_equation__no_text_ (image/png)
Which way does conventional current flow in this circuit? Which way do electrons move in the circuit? Image: circuit1.gif (image/gif)	Conventional current flows (anticlockwise) from positive to negative. Electrons move in the opposite direction (from negative positive). Image: circuit1.gif (image/gif)

Resource summary

	Created by lthistlewood2013 over 10 years ago