6. Which of the d.c. motor is not used in driving the belt connected loads ?
(A) shunt motor
(B) differentially compound motor
(C) cumulatively compound motor
(D) series motor
7. If the applied voltage to a d.c. motor is 220 V, then the back e.m.f., for maximum power developed is:
(A) 220 V
(B) 110 V
(C) 210 V
(D) 440 V
8. The unit of m.m.f. (magneto motive force) is :
(A) Ampere – meter
(B) Ampere turn /meter
(C) Wb/m2
(D) Ampere turn – meter
9. A 2 kW water heater operates 8 hrs per day. If cost of each unit is ₹ 3.00 per unit, then calculate the total bill for one month (30 days), assuming the charges for first 100 units are nil.
(A) ₹1140.00
(B) ₹ 1440.00
(C) ₹ 1740.00
(D) ₹840.00
10. From no-load speed to full-load speed, the torque of a 3-phase synchronous motor :
(A) first remains constant & then decreases
(B) remains constant throughout
(C) always decreases
(D) always increases