Oscillations
Amplitude
Maximum displacement from equilibrium position is
When too many people stand on a bridge it collapses, why?
Due to increase in stress
the ratio of 1 to square root of epsilon not and mue not is
velocity of light
Heisenberg's uncertainity principle
delta x . delta px = h cross
Fermi Energy
The energy of the electrons at top most filled level at 0 K
sine curve
Displacement-time graph depicting an oscillatory motion is
What will happen to the elastic property of Gold when Potassium is added to gold
The elastic property of gold increases
Find the force that exists in an electromagnetic wave.
a) Electrostatic force
b) Magnetostatic force
c) Lorentz force
d) Electromotive force
In an electromagnetic wave, the force of the electric and magnetic field both coexist. This is given by F = qE + q(v x B). It is called Lorentz force.
Matter waves
Waves associated with electrons
Temperature co-efficient of semiconductor
Negative
The circular motion of a particle whose speed is constant is
Uniform circular motion is a periodic motion but not simple harmonic.
Isotropic
The materials which have the same elastic properties in all directions
Two charges 1C and -4C exists in air. What is the direction of force?
Since the charges are unlike, the force will be attractive. Thus the force directs from 1C to -4C
Quantum of electromagnetic energy
Photon
charge carriers produced in intrinsic semiconductors
impure atoms
Which one of the following represents simple harmonic motion?
a) Acceleration = kx
b) Acceleration = k0 x+k1 x2
c) Acceleration = -k(x+a)
d) Acceleration = k(x+a)
Acceleration = -kX, X = x+a
Thus the acceleration is proportional to displacement and acts in its opposite direction. Hence, acceleration = -k(x+a) represents simple harmonic motion.
Elastic limit
The body will regain it is previous shape and size only when the deformation caused by the external forces, is within a certain limit.
The divergence of the vector xi + yj + zk.
3
Wave function
Contains all the possible information about the particle.
P-type semiconductor
P-type semiconductor is obtained by doping an intrinsic semiconductor with trivalent impurity.
In SHM, When v is maximum, a is
For a constant force, a rope breaks due to stress. Which of the following is useful to reduce the stress?
a) Increase the length of the rope
b) Apply small force
c) Increase the cross sectional area of the rope
d) Use a different material of rope
Stress = Force/Area
For a constant force, if the area is small, stress is large. If the area is large, stress is small. Therefore by increasing the cross sectional area stress can be reduced considerably.
So Answer is Option (c)
Stoke’s theorem
Theorem uses the curl operation.
∫ A.dl = ∫Curl(A).ds,
Maser
microwave amplification by stimulated emission of radiation.
Before laser maser was used. This was based on Albert Einstein’s principle of stimulated emission. It was used in the atomic clock.
Quantum Field Effect Transistor (QFET)
It is a kind of field-effect transistor that takes advantage of quantum tunneling to greatly increase the speed of transistor operation by eliminating the traditional transistor's area of electron conduction which typically causes carriers to slow down by a factor of 3000.