Resistance

Question 1

What is electrical resistance

Answer 1

Resistance is the opposition to the flow of electric current in a conductor. It is measured in ohms (Ω).
Some materials or components, like filament lamps, show a changing resistance as current increases due to heating.

Question 2

What is Ohm’s Law and how do we calculate resistance?

Answer 2

Ohm’s Law states:
V = IR, where

V = Voltage (volts)

I = Current (amperes)

R = Resistance (ohms)

To calculate resistance:

R=V/I

Question 3

Why should an ammeter have very low resistance

Answer 3

So it does not affect the current in the circuit. A low resistance ensures accurate current measurement without causing voltage drops.

Question 4

Why should a voltmeter have very high resistance?

Answer 4

To prevent current from flowing through it, so it does not affect the voltage being measured across a component.