BE Mechanical Engineering Semester 1 (FE First Year) - University of Mumbai Question Bank Solutions for Applied Physics 1

State properties of matter waves.

Derive Bragg's condition for X-ray diffraction. Monochromatic X rays are
incident on a crystal. If the first order rejection is observed at an angle of 3.4•, at
what angle would second order reflection expected.

What is the probability of an electron being thermally excited to conduction
band in Si at 27cC.The band gap energy is 1.12 eV.

Explain cavitation effect. 

Explain with example how to determine crystal structure by Bragg’s X-ray spectrometer.

With energy band diagram ,explain the variation of fermi energy level with temperature in extrinsic semiconductor .

Discuss in details any three factors affecting acoustics of a hall with their
remedies.

What is Maglev? How it can have very high speed?

What is working principle of SQUID ? Explain how it is used to detect the magnetic field?

With energy band diagram , explain the variation of fermi energy level with impurity concentration in extrinsic semiconductor. 

What is the working principle of maglev? Explain how it can acquire high speed?

Show that group velocity of matter waves associated with a particle is equal to
the particle velocity(V_group=V_particle)

Find the depth of sea water from a ship on the sea surface it the time interval of two seconds is required to receive the signal back. Given that: temperature of sea water is 20℃, salinity of sea water is 10gm/lit. 

What is the significance of wave function ? derive the expression for energy eigen values for the free particle in one dimensional potential well.

Explain the formation of potential barrier across the unbiased p-n junction region

Draw the energy band diagram  of p-n junction diode in forward and reverse bias condition .

Arrive at Heisenberg’s uncertainty principle with single slit electron diffraction. An electron has a speed of 300n/sec with uncertainty of 0.01 %. Find the accuracy in its position.

With Heisenberg’s uncertainty principle prove that electron cannot survive in nucleus. An electron has a speed of 300m/sec. with uncertainty of 0.01% . find the accuracy in its position.

State application of Hall effect. In a Hall effect experiment a potential difference of 4.5 μV is developed across a foil of zinc of thickness 0.02mm when a current of 1.5 A is carrying in a direction perpendicular to applied magnetic field of 2 tesla. Calculate :-

• Hall coefficient for zinc.

•  Concentration of electron.

State the Hall effect. Derive the expression for Hall voltage and Hall coefficient with neat diagram.