Resistance

Question 1

What is resistance?

Answer 1

The resistance of an electrical component is defined as the ratio of the potential difference across the component to the current flowing through it.

Question 2

The S.I. Unit for Resistance is

Answer 2

Ω (ohm)

Question 3

Resistance can be calculated using

Answer 3

R=V/I
R - Resistance (Ω)
V - Potential difference (V)
I - Current (A)

Question 4

The V-I graphs of non-ohmic conductors

Answer 4

will not be straight lines that pass through the origin

Question 5

As the length of a wire INCREASES

Answer 5

the resistance of the wire INCREASES

Question 6

As the cross-sectional area of a wire INCREASES

Answer 6

the resistance of the wire DECREASES

Question 7

With regard to Resistivity of a material, good conductors have

Answer 7

low resistivity

Question 8

Relationship between Resistance, Resistivity, Length of wire and Cross-sectional area:

Answer 8

R=p*L/A

Question 9

As the temperature INCREASES

Answer 9

Resistance of most conductors INCREASES (except carbon and semiconductors)

Question 10

Effective Resistance of resistors connected in SERIES:

Answer 10

Sum (R1+R2+R3)

Question 11

Effective Resistance of resistors connected in PARALLEL:

Answer 11

1/Effective Resistance = 1/R1 + 1/R2 + 1/R3