Question

In a circuit,two resistor of 20 ohm and 4 ohm are connected in series.Find the total resistance.

Answer 1

Answer- The above question is from the chapter 'Electricity'.

Let's know about resistance.

Resistance- It is the property of a conductor, semi-conductor or insulator to resist the flow of charges.

R = V/I

where R = Potential difference between two end points and I = flow of current.

Resistance is generally measured in Ohms. (Ω)

R = $\frac{\rho \: * \: l}{A}$

where ρ = resistivity, l = length of material and A = area of material.

R ∝ l

R ∝ ρ

R ∝ 1/A

Resistors can be connected in basically 2 ways:

1. Series Combination

2. Parallel Combination

Concept used: In series combination,

Effective Resistance = Sum of all resistances ( R₁ + R₂ + _ _ _ + Rₙ)

where n = number of resistors connected.

Given question: In a circuit, two resistors of 20 ohm and 4 ohm are connected in series. Find the total resistance.

Answer: Let R₁ = 20 Ω

R₂ = 4 Ω

They are connected in series.

Total Resistance = R₁ + R₂

Total Resistance = 20 + 4 = 24 Ω

∴ Total Resistance = 24 Ω