Govt. Exams
In longitudinal waves, particles oscillate parallel to the direction of wave propagation, creating compressions and rarefactions
Wave velocity v = √(T/μ), where T is tension and μ is mass per unit length. It is independent of frequency and amplitude
Standing waves result from the superposition of two coherent waves traveling in opposite directions with the same frequency
For a string fixed at both ends, fₙ = nf₁ where n is the harmonic number. Second harmonic (n=2) has f₂ = 2f₁
In constructive interference, phase difference is 0° or 2πn. Resultant amplitude = A₁ + A₂
In transverse waves, particle oscillation is perpendicular to the direction of wave propagation, such as in electromagnetic waves and ripples on water
Using v = fλ, where v = 300 m/s and f = 150 Hz, λ = v/f = 300/150 = 2 m
Silicon has dominated modern rectifiers because of significantly lower reverse saturation current (leakage ~nA at room temperature vs ~µA for Ge), better temperature stability, and superior thermal properties. The extra 0.4V drop is offset by reduced losses in high-power applications.
The current gain β is the ratio of collector current to base current (I_c/I_b). For silicon transistors, typical β values range from 50 to 500.
Reverse bias strengthens the electric field across the junction, causing the depletion region to expand as more charge carriers are pulled away from the junction.
