Transformer MCQs
1.The secondary winding of which of the following transformers is always kept closed?
- Current transformer
- Voltage transformer
- Power transformer
- Step down transformer
2.If the supply frequency of a transformer increases, the secondary output voltage of the transformer?
- Increase
- Decrease
- Remain the same
- Any of the above
3.Power transformers are designed to have maximum efficiency at …
- Full load
- 50% load
- 80% load
- no load
4.The open-circuit test in a transformer is used to measure ….
- Copper loss
- Winding loss
- Total loss
- Core loss
5.The leakage flux in a transformer depends upon the value of …
- Frequency
- Mutual Flux
- Load current
- Applied Voltage
6.Lamination of the transformer core is made of …
- Cast Iron
- Silicon Steel
- Aluminum
- Cast Steel
7.Breather is provided in a transformer to …
- Absorb moisture of air during breathing
- provide cold air in the transformer
- The filter of transformer oil
- None of above
8.Which of the following losses varies with the load in the transformer?
- Core loss
- Copper loss
- Both core & copper loss
- None of the above
YouTube channel raulstutorial Transformer MCQs
9.A transformer transform …
- Current
- Voltage & current
- Frequency
- Voltage
10.Transformer core are laminated in order to ..
- Reduce hysteresis loss
- Reduce hysteresis & eddy current loss
- Minimize eddy current loss
- Copper loss
11.A transformer has negative voltage regulation when its load power factor is…
- Lagging
- Leading
- Unity
- Any of the above
12.The main purpose of performing short circuit test in a transformer is to measure its ..
- Copper loss
- Core loss
- Insulation Resistance
- Total loss
13.The short circuit test in a transformer is performed on ..
- Low voltage side
- High voltage side
- Either 1 & 2
- Both 1 & 2
14.Which of the following loss in a transformer is zero even at full load..
- Eddy current loss
- Core loss
- Copper loss
- Friction loss
15.In a transformer the resistance between its primary and secondary is ..
- Zero
- Infinite
- 1000 ohm
- 100 ohm
16.The efficiency of two identical transformers under load conditions can be determined by ..
- Short Circuit test
- Open Circuit test
- No Load test
- Back to Back test (Sumpner Test)
17.The transformer ratings are usually expressed in terms of ..
- KW
- KVAR
- KVA
- Volts
18.Which winding in a transformer has more number of turns?
- Secondary winding
- primary winding
- High voltage winding
- Low voltage winding
19.Oil is provided in an oil-filled transformer for ..
- Lubrication
- Insulation
- cooling
- both cooling and insulation
20.Iron loss in a transformer can be determined by
- Open circuit test
- Short Circuit test
- Both 1 & 2
- None of the above
21.The path of magnetic flux in a transformer should have …
- Low resistance
- Low reluctance
- High Resistance
- High Reluctance
22.The noise of the transformer is mainly due to ..
- Cooling fan
- magnetostriction in an iron core
- Mechanical vibration
- All of the above
23.In a transformer the primary flux is _______ secondary flux.
- Greater than
- Smaller than
- Either 1 & 2
- Equal to
24.What would happen if a transformer is connected to a DC supply?
- No effect
- Operate with high efficiency
- Damage the transformer
- Operate with low frequency
25.The friction loss in a transformer is..
- 20%
- 0%
- 50%
- more than 50%
26.In an Auto Transformer, The Primary and Secondary are _______Coupled.
- Electrically only
- Magnetically only
- Both electrically & magnetically
- None of the above
