This is the continuation of the Partial Notes on Radiologic Physics 2.

ELECTRIC CIRCUITS

• It results when the resistance is controlled and the conductor is made into closed path.

TWO BASIC KINDS OF ELECTRIC CIRCUIT

1. Series Circuit- all circuit elements are connected in a line along the same conductor -
2. Parallel Circuit- contains elements that are connected at their ends rather than lies in a line along conductor.

Ohm’s Law

• relationship in which describes the manner in which electric current behaves in an electric circuit.

V= IR

where; V= voltage
I= current
R= resistance

• Voltage- the product of resistance and current
• Resistance- is the ratio of electric potential across the circuit element to the current.
• The greater the resistance, the higher the voltage it requires.

ELECTRIC CURRENT

1. Direct Current- e- flowing in one direction along the conductor
2. Alternating Current- current in which e- oscillate back and forth

• also known as 60 Hz current

● X-ray tube only operates in direct current that’s why we need rectifiers to convert AC- DC

Electric Power- measured in watts (W)
P= IV, P= I²R

THREE ESSENTIAL COMPONENTS OF ELECTRIC CIRCUIT

1. Voltage
2. Current
3. Resistance

Related Posts:

1. Partial Notes on Radiologic Physics 2
2. Partial Notes on Radiologic Physics 2 Part III

ELECTRICITY AND MAGNETISM

Matter

• has mass and energy equivalence and may also have electric charges
• Electrically neutral which means, in the entire universe the total number of positive charge is equal to the total number of negative charge.

Electrification

• derived from the word electricity
• Can be created by contact, friction and induction
• Due to the movement of negative electric charges.

• The primary function of x-ray tube is to convert electric energy to EMR or x-rays.

Two Studies of Electric Charges

1. Electrostatics- the study of electric charges in stationary form.
2. Electrodynamics- the study of electric charges in motion.

Four Fundamental Properties of Matter

1. Mass
2. Form
3. Energy equivalence
4. Electric charge

2 Units of Electric Charges

1. electrons- the smallest unit of electric charge.
2. proton- positively charge particle.

● Earth- huge reservoir for stray electric charge.

ELECTROSTATICS

Four Electrostatics Law

1. Unlike charges attract, like charges repel.

● Electrostatic Force- the force of attraction between unlike charges or repulsion between like charges which is due to the electric field.

2. Coulombs’ Law- states that electrostatic force is directly proportional to the product of the electrostatic charges and inversely proportional to the distance between them.

3. Electric Charge Distribution- states that electric charge distribution is uniform through out or on the surface.

4. Electric Charge Concentration- states that electric charges are concentrated along the sharpest curvature of the surface.

ELECTRODYNAMICS

• Is also known as electricity

Electric Current - the flow of electron and occurs in many types of objects.

Conductors and Insulators

• Conductor- is a substance through which e- flow easily
• Insulator- any material that does not allow the flow of e- or inhibits the flow of electrons

Semi- conductors

• possesses two properties of a conductor and insulator.

Superconductivity

• the property of the material to exhibits no resistance below a critical temperature.

Four Electric States of Matter

1. Superconductors- possesses no resistance to electron flow (niobium and titanium)
2. Conductor- it obeys Ohms’ Law and requires a voltage (copper and aluminum)
3. Semi-conductor- can be conductive and can be resistive (silicon and germanium)
4. Insulators- do not permit e- flow (glass and rubber)

● 1 ampere= 1 flow of e-/sec

Related Posts:

1. Partial Notes on Radiologic Physics 2 Part II
2. Partial Notes on Radiologic Physics 2 PART III