Electrical & Electronics Engineering – May 2015

Part – A

    1. Define electric potential difference.
    2. Explain the function of conductor. In what forms is it used and where.
    3. Calculate the resistance of a 400 W bulb connected across 230 volts power line.
    4. What is the shunt resistance Rs needed to extend the range of 50Ω, 1-mA movement to 100 mA.
    5. If a rms voltage of 120 V is applied across a 100 ohms resistor. What would be its rms current?
    6. Show how two resistance A and B are connected in parallel across a battery
    7. What is magnetic saturation
    8. Calculate the capacitance of a capacitor with plate area of 50 cm2 and dielectric thickness of 0.5mm with air as dielectric
    9. What is the peak to peak value of a sine wave whose rms value is 10 volts

Part – B

Unit -I

    1. Describe frequency of an alternating voltage.
    2. The conductance of a wire at 100°C is one tenth its value at 25°C. If the wire resistance equals 10 ohms at 25°C. Calculate the resistance of the wire at 100°C.
    1. Explain the color coding for resistors. Also how the color coding determines the tolerance of resistor.
    2. A 60 volts source is connected across a 30 kilo-ohm resistance:
    3. Draw the schematic diagram
    4. How much current flows through the resistance?
    5. Give the color code of the resistance

Unit -II

    1. Define voltmeter.
    2. Explain the loading effect of the voltmeter.
  1. Use the method of mesh currents to solve for IR1 , IR2 , IR3 , VR1 , VR2 and VR3 in the circuit given below:
    Electrical & Electronics Engineering – May 2015 - Q5

Unit -III

    1. Explain why the terminal voltage of a battery drops with more load current.
    2. Explain the main parts of the electric motors.
    1. Explain in brief lead-acid wet cell.
    2. A6 volt lead-acid battery has an internal resistance of 0.01 Ohm. How much current will flow if the battery has a short circuit?

Unit -IV

    1. Explainable magnetic field.
    2. The flux density in an iron core is 0.5T if the area of the core is 10 cm2. Calculate the total number of flux lines in the core.
    1. What is meant by a dielectric material? Name four common dielectric materials where it is used.
    2. A microfarad capacitor C1 and a 10 microfarad capacitor C2 are in series with a constant 2 milli ampere charging current:
    3. After 4 seconds, how much charge is in C1 and in C2.
    4. How much is the voltage across C1 and across C2.

Unit -V

    1. Explain in brief about semiconductors,
    2. Define hole charge and hole current.
  1. Explain the concept of PN junction.

Attention : This exam questions are converted from the real exam paper to a digital text format by using an OCR Software that may made some mistakes, I reviewed it many times to correct it, But may still there some errors that I missed or misspelled, So if you detect an error or mistake PLEASE report by adding a comment or contact me.