Explore topic-wise MCQs in Design Electrical Machines.

This section includes 20 Mcqs, each offering curated multiple-choice questions to sharpen your Design Electrical Machines knowledge and support exam preparation. Choose a topic below to get started.

1.

What is the formula for the length of the tank?

A. length of the tank = external diameter of h.v winding + clearance on each side between the winding and tank along the width
B. length of the tank = external diameter of h.v winding * clearance on each side between the winding and tank along the width
C. length of the tank = external diameter of h.v winding + 2*clearance on each side between the winding and tank along the width
D. length of the tank = external diameter of h.v winding / 2*clearance on each side between the winding and tank along the width
Answer» D. length of the tank = external diameter of h.v winding / 2*clearance on each side between the winding and tank along the width
Discussion
2.

What is the formula for width of the tank for single phase transformers used?

A. width of tank = 2*distance between adjacent limbs + external diameter of h.v windings + 2*clearance between h.v windings and tank
B. width of tank = distance between adjacent limbs + external diameter of h.v windings + 2*clearance between h.v windings and tank
C. width of tank = 2*distance between adjacent limbs * external diameter of h.v windings + 2*clearance between h.v windings and tank
D. width of tank = distance between adjacent limbs * external diameter of h.v windings + 2*clearance between h.v windings and tank
Answer» C. width of tank = 2*distance between adjacent limbs * external diameter of h.v windings + 2*clearance between h.v windings and tank
Discussion
3.

Elliptical tubes with pressed radiators are increasingly been used.

A. true
B. false
Answer» B. false
Discussion
4.

What is the range of the diameter of the tubes used?

A. 50-60 mm
B. 60-70 mm
C. 70-80 mm
D. 50-70 mm
Answer» E.
Discussion
5.

An addition of 35 percent should be made to tube area of the transformers.

A. true
B. false
Answer» B. false
Discussion
6.

ELLIPTICAL_TUBES_WITH_PRESSED_RADIATORS_ARE_INCREASINGLY_BEEN_USED??$

A. true
B. false
Answer» B. false
Discussion
7.

WHAT_IS_THE_RANGE_OF_THE_DIAMETER_OF_THE_TUBES_USED??$

A. 50-60 mm
B. 60-70 mm
C. 70-80 mm
D. 50-70 mm
Answer» E.
Discussion
8.

What is the formula for the length of the tank?$

A. length of the tank = external diameter of h.v winding + clearance on each side between the winding and tank along the width
B. length of the tank = external diameter of h.v winding * clearance on each side between the winding and tank along the width
C. length of the tank = external diameter of h.v winding + 2*clearance on each side between the winding and tank along the width
D. length of the tank = external diameter of h.v winding / 2*clearance on each side between the winding and tank along the width
Answer» D. length of the tank = external diameter of h.v winding / 2*clearance on each side between the winding and tank along the width
Discussion
9.

What is the formula for width of the tank for single phase transformers used?$

A. width of tank = 2*distance between adjacent limbs + external diameter of h.v windings + 2*clearance between h.v windings and tank
B. width of tank = distance between adjacent limbs + external diameter of h.v windings + 2*clearance between h.v windings and tank
C. width of tank = 2*distance between adjacent limbs * external diameter of h.v windings + 2*clearance between h.v windings and tank
D. width of tank = distance between adjacent limbs * external diameter of h.v windings + 2*clearance between h.v windings and tank
Answer» C. width of tank = 2*distance between adjacent limbs * external diameter of h.v windings + 2*clearance between h.v windings and tank
Discussion
10.

What is the rating of the transformer for the voltage of above 11 kV upto 33 kV?

A. 1000-5000 kVA
B. less than 1000 kVA
C. above 1000 kVA
D. 100-500 kVA
Answer» C. above 1000 kVA
Discussion
11.

What is the rating of the transformer for the voltage of about 11 kV?

A. 1000-2000 kVA
B. 100-3000 kVA
C. 1000-5000 kVA
D. 100-500 kVA
Answer» D. 100-500 kVA
Discussion
12.

What is the formula for height of transformer tank?

A. height of transformer tank = Height of transformer frame + clearance height between the assembled transformer and tank
B. height of transformer tank = Height of transformer frame * clearance height between the assembled transformer and tank
C. height of transformer tank = Height of transformer frame / clearance height between the assembled transformer and tank
D. height of transformer tank = Height of transformer frame – clearance height between the assembled transformer and tank
Answer» B. height of transformer tank = Height of transformer frame * clearance height between the assembled transformer and tank
Discussion
13.

What is the formula for number of tubes?

A. number of tubes = (1/ 8 * area of each tube) * (total loss / temperature rise with tubes – 12.5 * dissipating surface)
B. number of tubes = (1* 8 * area of each tube) * (total loss / temperature rise with tubes – 12.5 * dissipating surface)
C. number of tubes = (1/ 8 * area of each tube) / (total loss / temperature rise with tubes – 12.5 * dissipating surface)
D. number of tubes = (1/ 8 * area of each tube) + (total loss / temperature rise with tubes – 12.5 * dissipating surface)
Answer» B. number of tubes = (1* 8 * area of each tube) * (total loss / temperature rise with tubes ‚Äö√Ñ√∂‚àö√ë‚àö¬® 12.5 * dissipating surface)
Discussion
14.

What is the formula for temperature rise with tubes?

A. temperature rise with tubes = total loss / dissipating surface*(12.5 + 8.8x)
B. temperature rise with tubes = total loss * dissipating surface*(12.5 + 8.8x)
C. temperature rise with tubes = total loss / dissipating surface / (12.5 + 8.8x)
D. temperature rise with tubes = total loss + dissipating surface*(12.5 + 8.8x)
Answer» B. temperature rise with tubes = total loss * dissipating surface*(12.5 + 8.8x)
Discussion
15.

What is the loss dissipated by tubes by convection, given area of the tubes = 3.5?

A. 12.3 W per 0c
B. 2.51 W per 0c
C. 5.3 W per 0c
D. 30.8 W per 0c
Answer» E.
Discussion
16.

An addition of 35 per cent should be made to tube area of the transformers?

A. true
B. false
Answer» B. false
Discussion
17.

How is the circulation of oil improved in tanks with tubes?

A. it can be improved by using dissipating heat
B. it can be improved by using more effective air circulation
C. it can be improved by using more effect power flow
D. it can be improved by using more effective heads of pressure
Answer» E.
Discussion
18.

What is the relation of the transformer surface with respect to dissipation of heat?

A. transformer surface has no relation with respect to dissipation of heat
B. transformer surface has minor changes with respect to dissipation of heat
C. transformer surface has major changes with respect to dissipation of heat
D. transformer surface has no change with respect to dissipation of heat
Answer» E.
Discussion
19.

What is the relation of the provision of tubes with respect to dissipation of heat?

A. the provision of tubes is directly proportional to the dissipation of heat
B. the provision of tubes is indirectly proportional to the dissipation of heat
C. the provision of tubes is directly proportional to square of the dissipation of heat
D. the provision of tubes is indirectly proportional to square of the dissipation of heat
Answer» C. the provision of tubes is directly proportional to square of the dissipation of heat
Discussion
20.

What is the usage of the tanks with tubes?

A. if the temperature rise with plain tank is very low
B. if the temperature rise with plain tank is very high
C. if the temperature rise is zero
D. if the temperature rise with plain tank exceeds the specific limits
Answer» E.
Discussion