Current and Potential Difference

3.1

Current and Potential Difference

	Electric field
	The region around a charged particle where any electric charge in the region will experience an electric force

The patterns of observed electric fields for positive charge and negative charge are as follows:

(a)	The direction of the electric force line avoids the positive charge.

(b)	The direction of the electric force line to negative charge.

	Electric field strength, E
	Electric force acting on a unit positive charge placed at the point.

	\(E=\dfrac{F}{q}\), where E = electric field strength, F = electric force, Q = quantity of electric charge

	\(E=\dfrac{V}{d}\), where E = electric field strength, V = potential difference, d = distance between plates

	Electric current, \(I\)
	Rate of flow of charge in a conductor

	\(I = \dfrac{Q}{t}\), \(I\) = current, Q = total charge, t = time

	Potential difference
	Work done in moving one coulomb of charge from one point to another.

	\(V = \dfrac{W}{Q}\) or \(V=\dfrac{E}{Q}\), where V= potential difference, W = work done, E = energy transferred, Q = amount of charges flowing

3.1

Current and Potential Difference

	Electric field
	The region around a charged particle where any electric charge in the region will experience an electric force

The patterns of observed electric fields for positive charge and negative charge are as follows:

(a)	The direction of the electric force line avoids the positive charge.

(b)	The direction of the electric force line to negative charge.

	Electric field strength, E
	Electric force acting on a unit positive charge placed at the point.

	\(E=\dfrac{F}{q}\), where E = electric field strength, F = electric force, Q = quantity of electric charge

	\(E=\dfrac{V}{d}\), where E = electric field strength, V = potential difference, d = distance between plates

	Electric current, \(I\)
	Rate of flow of charge in a conductor

	\(I = \dfrac{Q}{t}\), \(I\) = current, Q = total charge, t = time

	Potential difference
	Work done in moving one coulomb of charge from one point to another.

	\(V = \dfrac{W}{Q}\) or \(V=\dfrac{E}{Q}\), where V= potential difference, W = work done, E = energy transferred, Q = amount of charges flowing