Class 10, Science, Chapter-11, Lecture-1, Electric Current (Notes)
ELECTRIC CURRENT:
The quantity of charge flowing through a cross section of a wire per unit time is termed as the electric current.
Mathematically $$I\,\,\, = \,\,\,{Q \over t}$$ where I = magnitude of electric current
Q = quantity of charge flowing at a given point
t = time
S.I. Unit – ampere ( A )
Electric current is a scalar quantity
ONE AMPERE:
The flow of 1 coulomb of charge through a cross section of a wire in 1 second is 1 ampere of electric current.
1 A = 1 C s–1
POTENTIAL DIFFERENCE:
The amount of work done in moving a unit positive charge from one point to another in an electric field is termed as the potential difference between two points.
Mathematically $$V\,\,\, = \,\,\,{W \over Q}$$ Where, V = potential difference between two points
W = work done in moving charge
Q = quantity of charge moved.
ONE VOLT:
The potential difference between two points when 1 joule of work is done in moving 1 coulomb of charge from one point to another is called one volt.
$$1\,\,volt\,\,\, = \,\,\,{{1\,\,joule} \over {1\,\,coulomb}}$$
The condition necessary for flow of electric charge through a conductor:
Maintaining a potential difference across the terminal points of the conductor.
AMMETER:
A device which is used for measuring electric current flowing in a circuit is called an ammeter.
VOLTMETER:
A device which is used for measuring potential difference between two points is called a voltmeter.
GALVANOMETER:
A device which is used for detecting the presence and direction of electric current flowing in a circuit is called a galvanometer.
ELECTRICAL CIRCUIT:
A continuous path consisting of conducting wires and other resistors between the terminals of a battery along which an electric current flows, is called an electric circuit.
CIRCUIT DIAGRAM:
A diagram, which indicates how different components in a circuit have been connected by using the electrical symbols for the components, is called a circuit diagram.
