Forum

Communication Systems

Define amplitude modulation. What are the advantages and disadvantages of amplitude modulation in communication systems?

Semiconductors

Explain the concept of intrinsic and extrinsic semiconductors. What is the role of doping in extrinsic semiconductors?

Atoms

Describe Bohr’s postulates for the model of the hydrogen atom. How does this model explain the line spectrum of hydrogen?

Dual Nature of Matter and Radiatios

State Einstein’s photoelectric equation. Explain the terms involved and discuss the significance of the work function.

Nuclei

Define binding energy of a nucleus. How does it vary with the mass number of the nucleus?

Electromagnetic Waves

List the properties of electromagnetic waves. Describe their propagation in free space.

Wave Optics

Explain the phenomenon of diffraction. What is the condition for observing diffraction of light?

Optics

• Derive the mirror formula for a concave mirror. Explain the significance of each term in the formula.

Alternating Current

What is the root mean square (RMS) value of an alternating current? How is it related to the peak value of the current?

Electromagnetic Induction

State Lenz’s law and explain how it follows from the law of conservation of energy. Give an example of its application.