In series motor which of the following methods can be used for changing the flux per pole ?

Related Mcqs:

1. The emf induced in a coil by a changing magnetic flux may have unit as______________?

   A. ms-1A
   B. ms-2A-1
   C. kgms2A-1
   D. kgm2s-1A-1

2. Series motor is not suited for traction duty due to which of the following account ?

   A. Less current drain on the heavy load torque
   B. Current surges after temporary switching off supply
   C. Self relieving property
   D. Commutating property at heavy load

3. Two 3.3 kΩ resistors are in series and this series combination is in parallel with a 4.7 kΩ resistor. The voltage across one of the 3.3 kΩ resistors is 12 V. The voltage across the 4.7 kΩ resistor is_________?

   A. 24 V
   B. 12 V
   C. 0 V
   D. 6 V

4. Two 1.2 kΩ resistors are in series and this series combination is in parallel with a 3.3 kΩ resistor. The total resistance is____________?

   A. 138 Ω
   B. 1,389 Ω
   C. 5,700 Ω
   D. 880 Ω

5. In a series–parallel circuit consisting of R1 and R2 in series and connected in parallel with R3, if R1 opens, then R2‘s voltage will:___________?

   A. increase
   B. remain the same
   C. decrease
   D. cannot tell

6. A series resonant band-stop filter consists of a 68 Ω resistor, a 110 mH coil, and a 0.02 µF capacitor. The internal resistance, RW, of the coil is 4 Ω. Input voltage is 200 mV. Output voltage is taken across the coil and capacitor in series. What is the output voltage magnitude at f0?

   A. 1.1 mV
   B. 11.1 mV
   C. 111 mV
   D. 200 mV

7. ________________ motor is a constant speed motor?

   A. Synchronous motor
   B. Schrage motor
   C. Induction motor
   D. Universal motor

8. A wound rotor induction motor is preferred, as compared to squirrel cage induction motor, when major consideration is____________________?

   A. slop speed operation
   B. high starting torque
   C. low windage losses
   D. all of the above

9. An aeroplane of wingspan 10m flies from the equator towards the North Pole. The wings are perpendicular to the vertical component of the earths magnetic field (B = 4×10-5T). At maximum speed an emf of 96mV is induced across the wing tips. The maximum speed of the aeroplane is____________?

   A. 150msec-1
   B. 384msec-1
   C. 38.4msec-1
   D. 200msec-1

10. In ______________ the speed can be varied by changing the position of brushes?

    A. slip ring motor
    B. schrage motor
    C. induction motor
    D. repulsion motor