Sample Questions on Inductance Formula

Question 1: Define Inductance.

Answer:

Inductance is a property of an electrical conductor that causes it to resist changes in the electric current passing through it. Since inductance has N² in the formula, it means that the square of the number of turns in the conductor are directly proportional to the inductance present. However, an interesting fact is that even straight conductors carry inductance just very little in amount to be considerable.

Question 2: What is the SI unit of Inductance?

Answer:

SI unit of Inductance is the henry (H). The discovery of inductance is credited to Faraday, however, the introduction of self inductance for a single circuit was first introduced by Henry. Therefore, the unit of inductance is dedicated to the scientist’s name.

Question 3: Determine the self-inductance of a 210-turn solenoid with a cross-sectional area of 17 cm² and a length of 66.2 cm.

Solution:

Given: μ = 4π × 10^-7N/A², N = 210 turns, A = 17 × 10^-4 m², l = 66.2 × 10^-2 m

Since,

L = μN²A/l

∴ L = ((4π × 10^-7) × (210)² × (17 × 10^-4))/(66.2 × 10^-2)

∴ L = 0.0001422

∴ L = 14.22 × 10^-5 H

Question 4: What is the corresponding resistance when 16H, 10H, and 21H inductors are joined in series?

Solution:

Given: L₁ = 16 H, L₂ = 10 H, L₃ = 21 H

Since,

L = L₁ + L₂ + L₃ 

∴ L = 16 + 10 + 21

∴ L = 47 H

Question 5: A circuit is connected to a 61 H inductor, and a frequency of 240 Hz is provided. calculate the reactance?

Solution:

Given: f = 240 Hz, L = 61 H

Since,

X = 2πfL

∴ X = 2 × 3.14 × 240 × 61

∴ X = 91939 ohm

Question 6: What is the corresponding resistance when 26H, 16H, 21H, and 30H inductors are connected in parallel?

Solution:

Given: L₁ = 26 H, L₂ = 16 H, L₃ = 21 H, L₄ = 30 H

Since,

1/L = 1/L₁ + 1/L₂ + 1/L₃ + 1/L₄ 

∴ 1/L = 1/26 + 1/16 + 1/21 + 1/30

∴ 1/L = 0.03 + 0.06 + 0.04 + 0.03

∴ 1/L = 0.16 H

∴ L = 6.25 H

Inductance is a term that every physics student should be familiar with. It has its own formula and is frequently combined with resistance and capacitance. Oliver Heaviside first coined the phrase in 1886. In addition, we use the L to represent inductors on circuit diagrams and inductance in equations, in honor of the eminent physicist Heinrich Let’s learn about the Inductance formula and how to use it to determine the inductance of any item.