can anyone explain me electricity of class 10th?
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Electricity
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Electric Current and Electric Circuit
Electric Current: The flow of electric charge is known as electric current. Electric current is carried by moving electrons through a conductor.
By convention, electric current flows in opposite direction to the movement of electrons.
Electric Circuit: Electric circuit is a continuous and closed path of electric current.
Expression of Electric Current: Electric current is denoted by letter ‘I’. Electric current is expressed by the rate of flow of electric charges. Rate of flow means the amount of charge flowing through a particular area in unit time.If a net electric charge (Q) flows through a cross section of conductor in time t, then;
Electric Current
(
I
)
=
Net charge
(
Q
)
Time
(
t
)
Or,
I
=
Q
t
Where,I is electric current,Q is net charge and t is time in second.
SI unit of Electric Charge and Current:
SI unit of electric charge is coulomb (C).
One coulomb is nearly equal to
6
×
10
18
electrons. SI unit of electric current is ampere (A). Ampere is the flow of electric charges through a surface at the rate of one coulomb per second. This means if 1 coulomb of electric charge flows through a cross section for 1 second, it would be equal to 1 ampere.
Therefore;
1
A
=
1
C
1
s
Small quantity of Electric Current: Small quantity of electric current is expressed in milliampere and microampere. Milliampere is written as mA and microampere as μA
1mA (milliampere)
=
10
−
3
A
1μA(microampere)
=
10
−
6
A
Ammeter: An apparatus to measure electric current in a circuit.
Example 1: Find the amount of electric charge flowing through the circuit if an electric current of 5 A is drawn by an electric appliance for 5 minute.
Solution: Given, electric current (I) = 5 A
Time (t) = 5 minutes =5×60=30o s
Electric charge (Q) =?
We know; I=QtOr, Q=I×tOr, Q=5A×300s=1500C
Example 2: If a current of 2 ampere is drawn for 1 hour through the filament of a bulb, find the amount of electric charge flowing through the circuit.
Solution: Given, electric current (I) = 2 A
Time (t) = 1 hour =1×60×60s=3600s
Electric charge (Q) =?
We know that
Q=I×t
Therefore, Q=2A×3600s=7200C