$A$ $60\, W$ load is connected to the secondary of a transformer whose primary draws line voltage. If a current of $0.54\, A$ flows in the load,what is the current in the primary coil? Comment on the type of transformer being used.

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(0.27 A) Given: Load power $P_{S} = 60\, W$,Secondary current $I_{S} = 0.54\, A$,Primary voltage $V_{P} = 220\, V$ (standard line voltage).
Step $1$: Calculate the secondary voltage $V_{S}$.
$P_{S} = V_{S} I_{S} \implies V_{S} = \frac{P_{S}}{I_{S}} = \frac{60}{0.54} \approx 111.1\, V \approx 110\, V$.
Step $2$: Determine the transformer type.
Since $V_{S} < V_{P}$ $(110\, V < 220\, V)$,the transformer is a step-down transformer.
Step $3$: Calculate the primary current $I_{P}$ using the ideal transformer relation $V_{P} I_{P} = V_{S} I_{S}$.
$I_{P} = \frac{V_{S} I_{S}}{V_{P}} = \frac{60}{220} \approx 0.27\, A$.
Thus,the current in the primary coil is $0.27\, A$ and it is a step-down transformer.

Explore More

Similar Questions

How does a transformer affect the voltage and current?

Difficult
View Solution

$A$ step-up transformer has a transformation ratio of $3:2$. What is the voltage in the secondary coil if the voltage in the primary coil is $30\, V$?

The number of turns in the primary coil of a transformer is $1000$ and in the secondary coil is $3000$. If $80 \ V$ a.c. is applied to the primary,the potential difference per turn of the secondary coil is: (in $V$)

The primary and the secondary coils of a transformer contain $10$ and $100$ turns, respectively. The primary coil is connected to a battery that supplies a constant voltage of $1.5 \, V$. The voltage across the secondary coil is .................. $V$.

What is a transformer? Write its principle and describe its construction.

Difficult
View Solution

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo