Basic Electrical Engineering ,Question Paper of BE 1 and 2 Semester,Download Previous Years Question Paper 1

S.B. Roll No………

BASIC ELECTRICAL ENGINEERING

2^nd Exam/ECE/CS/6125/2561/0064/Dec’11

Time: 3 Hrs.                                                                           Max. Marks: 75

SECTION-A

Q1.    Fill in the blanks:

(a) The unit of magnetic flux density is …………

(b) If ‘n’ identical resistances are connected in series, their total value is K? when these are connected in parallel their effective value is ……….

(c) The resistance of a wire is 2? If the diameter of wire is reduced to half, keeping the length same, then the resistance will be………….

(d) The power factor of an A. C. circuit is equal to ……………

(e) Frequency of D. C voltage is ……….

(f) The unit of  coefficient of coupling is ………….

(g) The unit of magnetic flux density is ………….

(h)For battery charging ………… supply is required.

(i) If 18 resistances, each of 36 W are connected in parallel, then effective resistance will be …………

(j) The power drawn by pure inductance is …………….

SECTION-B

Note:           Attempt any five questions.

Q2.    (i) Give the merits and demerits of nuclear power plant.

(ii) Define self and mutually induced emfs?

(iii) Draw and explain phazor diagram for the R-L series circuit.

(iv) Explain hysteresis loss.

(v) What is constant current source and draw characteristics of an ideal current source.

(vi) A resistor of 100W is connected in series with a 56mF capacitor to a supply at 230 V, 50Hz. Find the impedance, the current, the phase angle, the pf and the voltage across the resistor and the capacitor.

(vii) What do you mean by form factor and peak factor?

SECTION-C

Note:           Attempt any three questions.

Q3.    Find the impedance, current and the power factor of the following series circuits and draw the corresponding phazor diagram.

(i) R and L

(ii) R and C

In each case the applied voltage is 200volt , the frequency is 50Hz, R=10 ohm, L=50m H; C=100?F.

Q4.    (a) What are the various precautions to be observed for obtaining longer life and better efficiency of  lead acid battery.

(b) Define flux, mmf, reluctance and  permeability in magnetic circuits.

Q5.    Compare electric and magnetic circuits. What do you mean by power factor? What is its importance?

Q6.    Discuss hydro power plant with the help of schematic diagram.

S.B. Roll No……..

APPLLIED CHEMISTRY- II

2^nd Exam/Common/2254/Dec’11

Time: 3 Hrs.                                                                           Max. Marks: 75

Note:          Answer all section A questions on 1^st/2^nd page of answer booklet only. Write only correct answer (s)with power question number. Number in brackets against each question indicates marks.

SECTION-A

1.       Fill in the blanks (I to vii) & State True or False (viii to xv)

(i) Extraction of metal from its chief are at high temperature is known as ………. Metallurgy.

(ii) Aluminium alloy used to manufacture permanent magnets is ………….

(iii) It is necessary to cover available surface completely in……….. coating of base metal by protecting metal.

(iv) When a Fe-rod is kept in contact with Zn-rod then, Fe-rod can act as………..

(v) If 10L of a liquid fuel is burnt to produce QkJ heat then, calorific value of fuel is ……….. kJ/L.

(vi) Coal is covered into gasoline by heating carbon and hydrogen in presence of ….catalyst.

(vii) ………… number is used for rating diesel fuel.

State True or False (viii to xv)

(viii) Pour point and cloud point of lubricating oil are always same.

(ix) Total acid number (TAN) of lubricating oil must be minimum.

(x) Pigmented varnish is called paint.

(xi) Pyrex glass is used in making laboratory apparatus.

(xii) Harding of natural rubber by heating with sulphur is vulcanization of rubber.

(xiii) Nylon 6, 6 is an addition polymer.

(xiv) Deforestation causes air pollution.

(xv) Tree plantation on both sides of roads can reduce noise pollution.

SECTION-B

Attempt all questions.

2.       (a) Explain electrolytic refining of crude metal, with neat diagram of electrolytic tank.

Or

(b) Explain the corrosion of iron by hydrogen evolution mechanism with help of neat diagram.

Or

Explain the corrosion of iron by oxygen absorption mechanism with help of neat diagram.

3.       (a) What do you mean by passivity?

Or

What is corrosion? How it is different from erosion.

(b) What petrol fuel is rated by octane number? Explain.

Or

What is water gas? How it is manufactured? Give two application of it.

4.       (a) Calculate the calorific value of sample of coal 10 kg of which produces 1000kJ of heat on complete combustion.

(b) Define oiliness, viscosity and viscosity index, flash and fire point of lubricating oil.

Or

Define coke number, total acid number (TAN), aniline point, iodine and saponification value of lubricating oil.

5.       (a) Give the chemical composition and two applications of borosilicate glass.

Or

Give chemical composition of soda glass and two applications.

Or

(b) What is enamel? Name the constituents of enamels.

(c) Name the unit in which sewage water pollution and sound pollutions are measured.

6.       (a) Give one example to homo polymer and copolymer.

(b) Distinguish thermoplastics and thermosetting plastics.

Or

What is vulcanistion of rubber? Mention advantages of vulcanized rubber.

(c) Name green house gases. What effect they cause to the atmosphere?

SECTION-C

Attempt all questions.

7.       (a) Describe extraction of iron form haematite (Fe₂O₃) ore in blast furnace with chemical reactions at various zone with neat diagram of blast furnace.

Or

What is importance of “G” value of metal oxides? Explain usefulness of Ellingham’s diagrams in metallurgical operations.

State Pilling-Bedworth rule and mention its importance.

8.       (a) What is chromising?

(b) What is cetane number? Discuss the relation between cetane and chemical constituent of fuel.

Or

A 5g fuel sample is completely burnt in a bomb calorimeter containing 2000g water and 110g water equivalent of calorimeter causes 1.5⁰ rise in temperature. Calculate higher calorific value of fuel.

(c) What is the main constituent of biogas? Give applications of biogas.

(d) What are super conductors? Give examples.

9.       (a) What is hydrodynamic lubrication? Explain.

Or

Explain boundary lubrication mechanism.

(b) What are refractories? Give examples each type.

(c) What are adhesives? Give the user of araldite.

(d) What is PVC? How it is manufactured? Give an important application of PVC.

Or

What is polymerization? Give example to condensation polymer.