Electricity, Magnetism, and Electromagnetism

These flashcards cover key concepts and definitions from the lecture on Electricity, Magnetism, and Electromagnetism, designed to help students prepare for their upcoming exam.

What is the primary function of the x-ray tube?

To convert electrical energy to electromagnetic energy.

What percentage of electrical energy in an x-ray tube becomes heat?

99% of the electrical energy is converted into heat.

What are the smallest units of electric charge?

The electron and proton.

What is Coulomb's Law?

The electrostatic force between two charges is directly proportional to the product of their magnitudes and inversely proportional to the square of the distance between them.

How is electrification created?

By contact, friction, and induction.

What is the definition of a conductor?

A substance through which electrons easily flow.

What is Ohm's Law?

The voltage across a circuit is equal to the current times the resistance (V = IR).

What characterizes direct current (DC)?

Electric current flows in one direction through a conductor.

What is the difference between AC and DC?

AC (Alternating Current) involves electrons oscillating back and forth, while DC (Direct Current) flows in one direction.

What is Faraday's Law?

An electric current is induced in a circuit when some part of that circuit is in a changing magnetic field.

What affects the magnitude of induced electric current according to Faraday's Law?

The strength of the magnetic field, the velocity of the magnetic field movement, the angle of the conductor to the magnetic field, and the number of turns in the conductor.

What is the SI unit of magnetic field strength?

Tesla (T).

What is the role of an induction motor in an x-ray tube?

It powers the rotating anode of the x-ray tube.

What does a transformer do?

It transforms electric potential and electric current into higher or lower intensity without converting one form of energy to another.

What is the transformer law formula?

V₁/N₁ = V₂/N₂, known as the turns ratio.

If the primary side of a transformer has 600 turns and the secondary side has 300,000 turns, what is the turns ratio?

500:1.

What happens to the voltage if there are 125 turns on the primary side and 90,000 turns on the secondary side with 110 V applied to primary?

79,200 V (or 79.2 kV) is induced in the secondary winding.