Electrical Engineering - Transformers - Discussion
Discussion Forum : Transformers - General Questions (Q.No. 12)
12.
In a certain loaded transformer, the secondary voltage is one-fourth the primary voltage. The secondary current is
Discussion:
27 comments Page 1 of 3.
Srinivas said:
1 decade ago
To make transformer power is constant the current increases with decreasing the voltage for step down transformers. And it is decreases with increasing the voltage for step up transformers.
Zia said:
1 decade ago
Voltage and current are inversely propotional for transformer.
MANGALA PRASAD VASU said:
1 decade ago
Ans:- (B).
Because 'V' is directly proportional to 'i'.
Where 'V' is voltage & 'i' is current flow in ckt.
Because 'V' is directly proportional to 'i'.
Where 'V' is voltage & 'i' is current flow in ckt.
Azhar Ansari said:
1 decade ago
V1/V2= I2/I1
But V2=.025V1
Vi/0.25Vi= I2/I1
4=I2/I1
4I1= I2
But V2=.025V1
Vi/0.25Vi= I2/I1
4=I2/I1
4I1= I2
Ramashankar said:
1 decade ago
Suppose the pri.voltage(V1)=100 V
i.e the sec.voltage(V2)=(1/4)*pri.voltage(V1)
=(1/4)*100 =25 V
Actually we know the formula as,
V2/V1=N2/N1=I1/I2=K
i.e Turns ratio(K)=V2/V1=25/100=1/4=0.25
so, I1/I2=K=1/4
or, I2=4*I1 =4*Primary current
i.e sec. current equal to four times the pri. current
i.e we
i.e the sec.voltage(V2)=(1/4)*pri.voltage(V1)
=(1/4)*100 =25 V
Actually we know the formula as,
V2/V1=N2/N1=I1/I2=K
i.e Turns ratio(K)=V2/V1=25/100=1/4=0.25
so, I1/I2=K=1/4
or, I2=4*I1 =4*Primary current
i.e sec. current equal to four times the pri. current
i.e we
Aniket said:
1 decade ago
Mangala Prasad Vasu is wrong. In transformer ckt, the current is inversely proportional to the voltage. Because this is an inductive circuit & we all know that in inductive circuit current lags the voltage.
Only for that reason if the primary voltage of the transformer is 4 times the secondary voltage, the secondary current will be 4 times the primary current.
Only for that reason if the primary voltage of the transformer is 4 times the secondary voltage, the secondary current will be 4 times the primary current.
Mohan said:
1 decade ago
Given that V2=(1/4)V1
we know that V2/V1=I1/I2
therefore I1/I2=1/4
So I2=*I1
we know that V2/V1=I1/I2
therefore I1/I2=1/4
So I2=*I1
Suresh said:
1 decade ago
In transformer power is maintained constant i.e., v*i product should be same. , as we increases for n times I decreases for n times vice-versa.
Aparna said:
1 decade ago
Thanks Aniket.
Sita said:
1 decade ago
E2/E1=I1/I2
(1/4)E1/E1=I1/I2
I2=4I1
(1/4)E1/E1=I1/I2
I2=4I1
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