Design of Electrical Machines Practice Test 10

1. What happens in the rotating electrical machine?

the rotor slots are rotating

the rotor remains stationary

armatures are slotted and results in the movement of rotor

armatures are slotted

2. The mechanical parts design is very much important in which type of machines?

medium speed machines

low speed machines

low voltage machines

high speed machines

3. What is the frame used in the standard frames?

mechanical structure required to house a stator of given outside length

set of standard values

mechanical structure required to house a rotor of given outside diameter

mechanical structure required to house a stator of given outside diameter

4. What is the formula to obtain the hysteresis loss devised by Steinmetz?

hysteresis loss = 1/hysteresis coefficient * frequency of magnetization * (maximum flux density)^{steinmetz coefficient}

hysteresis loss = hysteresis coefficient * frequency of magnetization / (maximum flux density)^{steinmetz coefficient}

hysteresis loss = hysteresis coefficient / frequency of magnetization * (maximum flux density)^{steinmetz coefficient}

hysteresis loss = hysteresis coefficient * frequency of magnetization * (maximum flux density)^{steinmetz coefficient}

5. What is the formula of the flux density in the gap at a distance ‘x’ from the centre of the pole?

flux density in the gap at a distance ‘x’ from the centre of the pole = length of air gap at the centre of pole * length of air gap at a distance ‘x’ from the centre of the pole / maximum flux density in air gap

flux density in the gap at a distance ‘x’ from the centre of the pole = length of air gap at the centre of pole * length of air gap at a distance ‘x’ from the centre of the pole * maximum flux density in air gap

flux density in the gap at a distance ‘x’ from the centre of the pole = 1/ length of air gap at the centre of pole * length of air gap at a distance ‘x’ from the centre of the pole * maximum flux density in air gap

flux density in the gap at a distance ‘x’ from the centre of the pole = length of air gap at the centre of pole / length of air gap at a distance ‘x’ from the centre of the pole * maximum flux density in air gap

6. What is the formula of the specific electric loading?

specific electric loading = total armature ampere conductors / armature periphery at air gap

specific electric loading = total armature ampere conductors * armature periphery at air gap

specific electric loading = total flux around the air gap / area of flux path at the air gap

specific electric loading = total flux around the air gap * area of flux path at the air gap

7. What are the equations that are to be satisfied by flux patterns?

Laplace and Poisson equation

Gauss equation

Poisson equation

Laplace equation

8. What is the formula for the rms value of the magnetizing current?

rms value of the magnetizing current = maximum magnetizing current * peak factor

rms value of the magnetizing current = maximum magnetizing current / peak factor

rms value of the magnetizing current = maximum magnetizing current - peak factor

rms value of the magnetizing current = maximum magnetizing current + peak factor

9. What series is used to analyze the field form?

z-series

fourier transform

z-transform

fourier series

10. What are the factors the overhang leakage reactance is obtained?

shape of the overhang

length of the overhang along with the shape of the overhang

diameter of the overhang

length of the overhang