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B2F1002 Pages:3

b. Determine the current drawn from the supply using start delta conversion. (5)

a. A steel ring of 20 cm? cross-section having a mean diameter of 50 cm is wound
uniformly with 500 turns. Flux density of 1.0 Wb/ ന is produced by 4000 ampere
turns per metre. Calculate (i) the inductance (ii) the exciting current and (iii) the
inductance when a gap of 1 mm long is cut in the ring, the flux density being 1.0 Wb/
172. Neglect leakage and fringing. (7)

b. A conductor of length 0.5 m moves in a uniform magnetic field of density 1.1 T at
a velocity of 30 m/s. Calculate the induced voltage in the conductor when the
direction of motion is inclined at 60° to the direction of the field. (3)

. ೩. Derive the form factor of a pure sinusoidal wave form. (5)

b. An alternating voltage of (80 + j60) V is applied to a circuit and the current flowing
is (-4 + j10) A. Find (i) the impedance of the circuit, (൪) the power consumed and (0)
the phase angle. (5)

. 2. Each phase of a delta connected load has a resistance of 25 Q and an inductance of

0.15 H. The load is connected across a 400 V, 50 Hz, three phase supply. Determine
the line current, power factor and power consumed. (5)

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