Fundamental Concepts in Classical Mechanics Physics

Physical Quantities and Measurement

Physical Quantity: A property of a body or phenomenon that can be measured and expressed by a number and a unit (e.g., 5 m, 10 s, 3 kg). It allows us to describe physical laws quantitatively. A physical quantity is defined either by specifying how it is measured or by stating how it is calculated from other measurable quantities.

Unit of Measurement: A standard reference used for comparing quantities of the same kind. Example: meter (m) for length, second (s) for

Read More

Electromagnetic Waves, Sound & Wave Properties

Electromagnetic Waves, Sound & Wave Properties

Electromagnetic waves used in communication with wavelengths between about 1 cm and 20 cm are called (microwaves).

Electric signals that have only two possible values (on and off) are (digital signals).

A(n) (photon) is an electromagnetic wave that behaves like a particle.

Electromagnetic radiation with wavelengths between 400 and 750 billionths of a meter that can be detected by the human eye is (visible light).

A system of satellites, ground monitoring

Read More

Semiconductor Electronics, P–N Junctions, Atomic Models & AC Physics

Semiconductor Electronics

Semiconductor

Semiconductor — These materials whose electrical conductivity lies between a conductor and an insulator are called semiconductors. At absolute zero they behave as insulators and at room temperature they behave as conductors.

Examples: Ge, Si, GaAs, CdS, CdSe, InP, etc.

Classification by Energy Band Theory

In solids there are three energy bands:

  • The lower band is completely filled by electrons and is called the valence band (VB).
  • The upper band is called the conduction
Read More

Electric Charge, Fields, Potential and Current

Electric Charge and Electric Field

Electric charge — it is a property of a body; charged bodies exhibit attraction and repulsion.

Electric field

Electric field — the sphere around a source charge in which a test charge would experience a force is called the electric field.

Electric field lines

Electric field lines — an electric field is represented by imaginary lines of force which are called electric field lines.

Properties of field lines

  • They are imaginary lines of force.
  • They are not closed (they
Read More

Electric Field, Potential, Capacitance & Current Notes

Chapter 1: Electric Field and Dipole

Electric Field

Electric field: The sphere around a source charge in which a test charge would experience a force is called the electric field.

Electric Field Lines

Electric field lines: An electric field is represented by imaginary lines of force which are called electric field lines.

Properties

  1. They are imaginary lines of force.
  2. In the case of a positive source charge they are radially directed outward.
  3. They are not closed lines.

Mathematical Definition of Electric Field

Mathematically

Read More

Physics Laboratory Experiments: Ohm’s Law, Diodes, and Magnetism

Experiments in Electricity and Magnetism

Experiment 1: Verifying Ohm’s Law and Determining Resistance

To observe the variation of potential difference (V) across a given resistance with varying current (I), draw the I-V curve, and find the value of the given resistance from the graph.

Apparatus and Materials

  • Battery
  • Ammeter
  • Voltmeter
  • Resistance (unknown)
  • Rheostat
  • Key
  • Connecting wires
  • Sandpaper

Theory

Ohm’s law states that, provided the temperature remains constant, the current (I) flowing through a conductor

Read More