BE Automobile Engineering Semester 1 (FE First Year) - University of Mumbai Question Bank Solutions

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.

Derive an expression for Hall voltage and Hall coefficient with neat labelled diagram.

Draw the I-V characteristics of a photo -diode. What is meant by dark current?

Distinguish between Type I and Type II superconductor.

What is photovoltaic effect? Explain the principle and working of solar cell.

An electron is confined in a box of dimension 1A°. calculate minimum uncertainty in its velocity.

Explain the principle, construction and working of Light Emitting Diode.

Write schrodinger’s time dependentand time independent wave equations of matter waves in one dimensional and state physical significance of these Equations. 

Derive Schrodinger time dependent wave equation for matter waves. 

Obtain one dimensional time dependent time independent Schrodinger equation.

A single phase transformer has 1000 turns on the primary and 200 turns on the secondary. The no load current is 3A at a power factor of 0.2 lag and the secondary current is 280A at a power factor of 0.8 lag. Neglect R₂ and X₂ calculate (1) Magnetizing component and loss component of no load current. (2) primary current (3) input power factor .Draw phasor diagram showing all the currents.

Find the node voltages 𝑽_𝟏,𝑽_𝟐 𝒂𝒏𝒅 𝑽_𝟑 and current through 0.5Ω

Find the RMS value of the waveform given below:-

A balanced 3 phase star connected load consists of three coils each consisting of R=6Ω and 𝑿𝑳= 8Ω . Determine the line current , power factor when the load is connected across 400V, 50Hz, supply

Describe the basic principle of operation of a single phase transformer and derive the emf equation.

Briefly explain the classification of DC machine.

Using the mesh analysis find the mesh current in the direction shown and also find the voltage across A and B terminals.

A resistance and a capacitor connected in series across a 250V supply draws 5A at 50Hz. When frequency is increased to 60Hz, it draws 5.8A. Find the values of R & C. Also find active power and power factor in both cases.

Draw the phasor diagram of a single phase transformer when it is loaded with a lagging power factor load.