1- A Transformer is designed to be operated on both 50 & 60 Hz frequency.For the Same rating, which one will give more out put; when,
a. Operates on 50 Hz
b. Operates on 60 Hz
2- In a Transformer , The primary flux is always _________ the secondary ( flux).
a. Greater then
b. Smaller then
c. Equal
d. Equal in both step up and Step down Transformer
3- What would happen if we operate a 60 Hz Transformer on 50 Hz Source of Supply.(and how can we do that?
a. Current will decrease (so increase the current)
b. Current will increase ( so decrease the current)
c. Current will be same in both cases.
d. No Effect ( We can do that without changing anything)
4- We can’t perform such an operation.
A Step-Up Transformer which has 110/220 turns.What would happen if we replace it with 10/20 turns? (because Turns ratio would be same in both cases)
a. induced E.M.F wold be same
b. Induced E.M.F would be decreased
5- The rating of transformer may be expressed in ____________.
a. kW
b. kVAR
c. kVA
d. Horse power.
6- What will happen if the primary of a transformer is connected to D.C supply?
a. Transformer will operate with low efficiency
b. Transformer will operate with high efficiency
c. No effect
7- Transformer may start to smoke and burn
What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage?
a. Current will be too much high
b. Transformer may start to smoke and burn
c. Eddy Current and Hysteresis loss will be excessive
d. No effect
8- What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 5 Hz (frequency) source of the same voltage?
a. Current will be too much low
b. Transformer may start to smoke
c. Eddy Current and Hysteresis loss will be excessive
d. No effect
9- A Step Up transformer _____________.
a. Step Up the level of Voltage
b. Step down the level of current
c. Step up level the power
d. Step up the level of Frequency
10- Under what condition is D.C supply applied safely to the primary of a transformer?
a. We can connect directly to DC. No condition required
b. We can’t connect to DC Supply
11- A High resistance should be connect in series with primary, but circuit will be useless.
The above statement is wrong
An Auto-transformer (which has only one winding) may be used as a ______?
a. Step-Up Transformer
b. Step-Down Transformer
c. Both Step-Up and Step-Down transformer
d. None of the above
12- E.M.F Equation of the Transformer is _________.
E1 = 4.44 f N1 Øm , E2=4.44 f N2 Øm
E1 = 4.44 f N1 Bm A , E2 = 4.44 f N2 Bm A
E1= 4.44 N1 Øm/T , E2=4.44 N2 Øm/T
All of the above
None of the above
13- The friction losses in Real Transformers are _________?
a. 0%
b. 5%
c. 25%
d. 50%
14- An Isolation Transformer Has Primary to Secondary turns ratio of __________.
a. 1 : 2
b. 2 : 1
c. 1 : 1
15- Can be any ratio
In an Auto Transformer, The Primary and Secondary are__________Coupled.
a. Only Magnetically
b. Only Electrically
c. Magnetically as well as Electrically
d. None of the above
16- A Transformer______________.
a. Changes ac to DC
b. Changes dc to AC
c. Steps up or down DC Voltages & Current
d. Steps up or down AC Voltages & Current
NTS Test Preparation for Analytical Reasoning question with solution,
Six Person A, B, C, D, E and F are sitting around a circular table facing the center, NTS old Ppaers, NTS old test, NTS test solution, Most repeating question
Statement: Six Person A, B, C, D, E and F are sitting around a circular table facing the center. 1. C is sitting exactly between A a...
Q-01: Between which two persons is D sitting
(a). F-B
(b). E-B
Q-02: Who is sitting opposite A?
(a). F
(b). C
(c). E
(d). None of these
Q-03: Which of the following A's neighbor to his right
(a). C
(b). F
(c). B
Q-04: Who is sitting opposite E?
(a). A
(b). B
(c). F
Q-05: Between which of two persons is F
(a). A-B
(b). B-E
(c). C-B
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