Magnetism- extra

What is a magnetic field?

A region of magnetic force

What type of fields are magnetic fields?

Three-dimensional

What is the Earth's magnetic field generated by?

Movement of molten iron

Match the source of the magnetic field with its mechanism:

Permanent Magnets ↔ Alignment of electron spins

Electromagnets ↔ Current flowing through coils

Earth's Magnetic Field ↔ Movement of molten iron

What is electromagnetism?

Interaction between electricity and magnetism

What is the name of the law that mathematically describes electromagnetic induction?

Faraday's Law of Induction

What is the formula for Faraday's Law of Induction?

E=-N*dΦ​/dt

What is a key difference between permanent magnets and electromagnets in terms of their magnetic field?

Constant vs. controllable

Steps in creating an electromagnet:

1⃣ Wrap a coil of wire around a magnetic core

2⃣ Pass an electric current through the coil

3⃣ The current generates a magnetic field

Match the factor affecting electromagnet strength with its effect:

More turns in the coil ↔ Increases magnetic field strength

Higher current ↔ Stronger magnetic field

Iron core ↔ Amplifies magnetic field

What is the key advantage of electromagnets over permanent magnets in magnetic cranes?

Controllable lift and release

What is electromagnetism?

Interaction between electricity and magnetism

What type of core material is commonly used in electromagnets?

Iron

What does the motor effect describe?

Force on current-carrying conductor

What is a current-carrying conductor in the motor effect?

A wire carrying electric current

Match the finger in Fleming's Left-Hand Rule with what it represents:

Thumb ↔ Force

First Finger ↔ Magnetic Field

Second Finger ↔ Current

Steps to apply Fleming's Left-Hand Rule

1⃣ Hold your left hand with thumb, first finger, and second finger at right angles

2⃣ Point your first finger in the direction of the magnetic field

3⃣ Point your second finger in the direction of the current

4⃣ Your thumb will point in the direction of the force

What device measures small currents using the motor effect?

Galvanometer

What is an electric motor?

Converts electrical to mechanical energy

Arrange the steps in how an electric motor converts electrical energy into kinetic energy.

1⃣ Electrical current flows through armature coils

2⃣ Motor effect generates a force

3⃣ Armature rotates due to the force

4⃣ Electrical energy is converted into kinetic energy

What is the role of a commutator in a DC electric motor?

Reverses current direction

What is the formula for the force acting on a current-carrying wire in a magnetic field?

F=BIL

Match the device with its energy conversion:

Electric Motor ↔ Electrical to Mechanical

Generator ↔ Mechanical to Electrical

What are the units for magnetic field strength?

Teslas (T)

What is the unit for electrical current?

Amperes (A)

Steps in the operation of an electric motor

1⃣ Current flows through the coil

2⃣ A force is produced due to the motor effect

3⃣ The armature rotates

4⃣ The commutator reverses the current

5⃣ Continuous rotation is maintained

Match the components of an electric motor with their functions:

Armature ↔ Coils of wire that rotate

Stator Magnets ↔ Create a magnetic field

Commutator ↔ Reverses current direction

Brushes ↔ Ensure electrical contact

Match the parameter with its corresponding symbol and direction in Fleming's left-hand rule:

Magnetic Field ↔ B, Index finger

Current ↔ I, Middle finger

Force ↔ F, Thumb

What material are brushes typically made of in DC motors?

Carbon or graphite