Chp14 : Current Electricity
Answer the following questions.
1. Define the term Electric Current?
Ans. “The rate of flow of electric charge through any cross-sectional area is called
Electric current”
Current = Charge/ time Or I = Q/t
Unit: SI unit of Current is Ampere (A).
2. What is the difference between Electronic current and Conventional current?
Ans. Electronic Current
The current due to motion of negative charges that flows from the negative terminal of the battery to the positive terminal in the electrical circuit is called Electronic current.
Conventional Current
The current due to motion of positive charges that flows from positive terminal of battery to its negative terminal is called Conventional current.
3. How can we differentiate between e.m.f and Potential difference?
Ans EMF
- Electromotive force is the total voltage in the battery.
- Electromotive force is always greater.
- EMF is only applicable to an electric field.
Potential Difference
- Potential difference is the work done in moving a charge against the electric field.
- Potential difference is always small.
- Potential difference is only applicable to magnetic, gravitational and electric field.
4. Define Ohm’s Law?
Ans. If V is the potential difference across the two ends of any conductor, then current I
will flow through it. The value of the current changes with the changes in potential
difference and explained by ohm’s law.
5. Define Resistance and its Units?
Ans. “The property of a substance which offers opposition to the flow of current through
it is called its Resistance.”
Unit : Its SI unit is ohm
6. Differentiate between insulators and conductors.
Ans: In parallel combination one end of each resistor is connected with positive terminal
of battery while the other end of each resistor is connected with the negative terminal of
battery.
1/Req = 1/R1 + 1/R2 + 1/R3
No comments:
Post a Comment