12.4 Inductance

• What is inductance measured in?

  Henries
• The formula for inductance (L) is (NΦ) / I
• What is the inductance of a coil with 100 turns, a current of 2A, and a magnetic flux of 0.01 Wb?

  0.5 H
• How does the permeability of the core material affect inductance?

  Increases inductance
• Mutual inductance occurs when a changing current in one coil induces a voltage in another nearby
• What is the formula for inductance (L)?

  L = (NΦ) / I
• Match the property with its definition:

  Mutual Inductance ↔️ Voltage induced in one coil by changing current in another

  Self-Inductance ↔️ Voltage induced in a coil by its own changing current
• Self-inductance is the property of a coil to induce a voltage in another nearby coil.

  False
• What is mutual inductance?

  Voltage induced in another coil
• What is one factor that affects mutual inductance?

  Permeability of the core
• Match the property with its description:

  Mutual Inductance ↔️ Voltage induced in another coil

  Self-Inductance ↔️ Voltage induced in the same coil
• A higher inductance in an RL circuit results in a longer time constant.


  True
• What is the analog of inductance in electrical circuits?

  Capacitance
• Match the variable in the inductance formula with its unit:

  L ↔️ Henry (H)

  Φ ↔️ Weber (Wb)

  I ↔️ Ampere (A)

  N ↔️ No unit
• Inductance increases with the coil's area
• What is the definition of self-inductance?

  Voltage induced in same coil
• What is mutual inductance defined as?

  Voltage induced in another coil
• Mutual inductance occurs within a single coil.

  False
• Self-inductance is described by Faraday's Law and Lenz's Law.


  True
• Arrange the following properties in a comparison between mutual inductance and self-inductance:

  1️⃣ Definition: Mutual inductance involves two coils, while self-inductance involves one

  2️⃣ Relationship: Mutual inductance is between two separate coils, while self-inductance is within a single coil

  3️⃣ Formula: Mutual inductance uses M = (N1Φ2) / I1, while self-inductance uses L = (NΦ) / I

  4️⃣ Unit: Both mutual inductance and self-inductance are measured in henries
• Mutual inductance is affected by the same factors as self-inductance
• In the formula for mutual inductance, N1 and N2 represent the number of turns in the coils.


  True
• The formula for self-inductance is L = (NΦ) / I.


  True
• What is the formula for the time constant in an RL circuit?

  τ = L/R
• What is the formula for the energy stored in an inductor?

  U = (1/2) LI²
• What does inductive reactance in an inductor oppose?

  Changes in current
• The energy stored in an inductor is measured in joules.
• Inductance is a consequence of Faraday's Law.


  True
• What does N represent in the inductance formula?

  Number of turns
• Inductance increases linearly with the number of turns in a coil.

  False
• Self-inductance is measured in henries.


  True
• What is the formula for mutual inductance between two coils?

  $M =$$\frac{N_{1}\Phi_{2}}{I_{1}}$
• The formula for mutual inductance (M) is M = (N1Φ2) / I1
• Inductance is measured in units called henries
• What are the three factors affecting the inductance of a coil?

  Number of turns, coil geometry, permeability
• What is the inductance of a coil with 100 turns, a magnetic flux of 0.01 Wb, and a current of 2A?

  0.5 H
• The formula for mutual inductance is M = (N1Φ2) / I1 = (N2Φ1) / I2
• Mutual inductance involves a voltage induced in one coil by a changing current in another coil.
• The time constant (τ) of an RL circuit is the time it takes for the current to reach 63.2% of its final value.
• In an RC circuit, the time constant is given by τ = RC.