electricity

Question 1

What is electric current?

Answer 1

The rate of flow of electric charge through any cross-section of a conductor.
SI unit- Ampere (A)
I(electric current) = q(charge)/t
measured by ammeter (series)

Question 2

What is potential difference?

Answer 2

Work done per unit charge in moving a unit positive charge from one point to another.
SI unit = volt (V)
V = W/q(charge) = joule per coulomb
voltmeter used to measure (connected in parallel)

Question 3

What does ohms law state?

Answer 3

V=IR

Question 4

What is resistance?

Answer 4

Resistance is the property of a conductor to resist the flow of electric charge.
R=V/I
SI unit = Ohm

Question 5

Factors on which resistance is dependent

Answer 5

R is proportional to the length of conductor
R is inversely proportional to area of cross-section (A)

R = p(resistivity)*l/A

Question 6

Define resistivity

Question 7

What is power?

Question 8

What is the heating effect of electric current?

Question 9

S.I. unit of resistivity

Answer 9

ohm-meter