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Step up transformer increases
Voltage
Current
Power
Frequency
Voltage
A step-up transformer is a static electromagnetic device designed to increase the voltage level of an AC signal. It operates by having a higher number of turns in the secondary winding compared to the primary winding.
A step-up transformer is a static electromagnetic device designed to increase the voltage level of an AC signal. It operates by having a higher number of turns in the secondary winding compared to the primary winding.
V1тАЛV2тАЛтАЛ=N1тАЛN2тАЛтАЛ=I2тАЛI1тАЛтАЛ тАФ Ideal transformation ratio
P=VтЛЕIтЛЕcos╧Х тАФ Power relation in AC circuits
The transformer operates on Faraday's Law of Electromagnetic Induction. Since the power input is approximately equal to the power output (PinтАЛтЙИPoutтАЛ), increasing the voltage across the secondary winding necessitates a proportional decrease in the current to satisfy the conservation of energy principle.
In a step-up transformer, the secondary voltage (V2тАЛ) is higher than the primary voltage (V1тАЛ).
Secondary current (I2тАЛ) is lower than the primary current (I1тАЛ) to maintain constant power.
Transformers do not change the frequency of the AC supply.
They operate strictly on the principle of mutual induction.
Reduces transmission losses (I2R) by stepping up voltage for long-distance power distribution.
Efficiently matches impedance in electrical circuits.
Cannot operate on DC supply.
Requires high-quality insulation for high-voltage secondary windings.
Power transmission substations.
X-ray machines.
Microwave ovens.
Option B is incorrect because current decreases when voltage increases in an ideal transformer.
Option C is incorrect because transformers are passive devices and do not generate power.
Option D is incorrect because the frequency remains constant as defined by the source frequency.
A is correct тАФ A step-up transformer increases the voltage level from the primary to the secondary winding.
Remember that transformers are constant power devices; if voltage is stepped up, current must step down proportionally to keep VтЛЕI constant.