Electricity
➣ Electric current:- the rate of flow of charges
➣ electric current and its direction
•Considered:- the flow of positive charges
•Conventional:- the flow of negative charges
Q
➣I = t
➣ SI unit of electric current is COULOMB (C).
➣ electric current is expressed as AMPERE (A) named after French
scientist Andre-Marie ampere.
➣ an instrument called ammeter measures electric current in a
circuit. It is always connected in series.
➣ The electrons move only if there is a difference in electric
pressure called the potential difference.
W
➣ V=
Q
➣The SI unit of potential difference is volt (V), named after an
Italian scientist Alessandro Volta.
➣ The potential difference is measured by a voltmeter. It is always
connected in parallel.
OHM’S LAW
The potential difference, V, across the ends of a given metallic wire
in an electric circuit is directly proportional to the current flowing
through it, provided its temperature remains the same. This is
called ohm’s law.
V ∝I
V
Or I
=Constant let constant = R
Or V =IR
➣ Electric current:- the rate of flow of charges
➣ electric current and its direction
•Considered:- the flow of positive charges
•Conventional:- the flow of negative charges
Q
➣I = t
➣ SI unit of electric current is COULOMB (C).
➣ electric current is expressed as AMPERE (A) named after French
scientist Andre-Marie ampere.
➣ an instrument called ammeter measures electric current in a
circuit. It is always connected in series.
➣ The electrons move only if there is a difference in electric
pressure called the potential difference.
W
➣ V=
Q
➣The SI unit of potential difference is volt (V), named after an
Italian scientist Alessandro Volta.
➣ The potential difference is measured by a voltmeter. It is always
connected in parallel.
OHM’S LAW
The potential difference, V, across the ends of a given metallic wire
in an electric circuit is directly proportional to the current flowing
through it, provided its temperature remains the same. This is
called ohm’s law.
V ∝I
V
Or I
=Constant let constant = R
Or V =IR
