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TUTOR MARKED ASSIGNMENT
BET-024
Electrical/Mechanical Engineering
Note : All questions are compulsory. Marks assigned to the questions have been shown in the bracket. Maximum Marks : 100Weightage : 30%Course Code : BET-024 Last Date of Submission : April 30, 2011DCLE (G)
Q.1 (a) If R = 20 , R2 = 10 , R3 = 8 and voltage cell of 60V connected across these for a connection shown in Figure 1, then calculate the current in all three resistors.
R1VR3R2I
Figure 1
(b) Define Ohm’s law. Derive a formula for heat produced in a conductor due to flow of current.
(5 + 5 = 10)
Q.2 (a) In the circuit shown in Figure 2, determine the current flowing through the 6 resistance.
Figure 2
(b) Write Kirchhoff ’s Voltage and Current laws.
(6 + 4 = 10)
Q.3 (a) Explain Maxwell’s Cork Screw rule.
(b) Illustrate Biot-Savart’s law and its application.
(c) What do you understand by magnetic flux?
(3 + 5 + 2 = 10)
Q.4 (a) State Lenz’s law and application of Eddy Currents.
(b) Find the magnitude of emf induced in a 200 turns coil with cross-sectional area of 0.08 m², if the magnetic field through the coil changes from 0.20 wbm- ² to 0.80 wbm- ² at a uniform rate over a period of 0.02 second.
(5 + 5 = 10)
Q.5 (a) Explain Second law of Electrostatics.
(b) Derive an expression for Capacitances of Capacitors connected in series and parallel connection.
(5 + 5 = 10)
Q.6 (a) Write merits of 3-phase system over 1-phase system.
(b) Deduce emf Equation for D.C Generator.
(c) A 240 volts DC shunts motor has armature resistances of 0.20 ohm and field resistances of 400 ohm. The normal speed is 1000rpm and the armature current is 40 ampere. What additional resistances should be added in the field to increase the speed to 1200 rpm. Assume that the armature current remaining same and magnetization curve is a straight line
(3 + 3 + 4 = 10)
Q.7 (a) State Boyle’s law and Charle’s law.
(b) 2 kg of air at pressure of 10 bar occupies a volume of 0.28 m³. This air is expanded to a
