Advertisements
Advertisements
Question
State the factors on which the frequency of the alternating e.m.f. depends.
Advertisements
Solution
The frequency of the alternating e.m.f. depends on the frequency of rotation of the coil.
RELATED QUESTIONS
A transformer converts 240 V AC to 60 V AC. The secondary has 75 turns. The number of turns in primary are _______.
(A) 600
(B) 500
(C) 400
(D) 300
State two ways through which the strength of an electromagnet can be increased.
Describe, with the help of a suitable diagram, the working principle of a step-up transformer. Obtain the relation between input and output voltages in terms of the number of turns of primary and secondary windings and the currents in the input and output circuits.
Mention the two characteristic properties of the material suitable for making core of a transformer.
Why is the core of a transformer made of soft iron?
A 200V/120V step-down transformer of 90% efficiency is connected to an induction stove of resistance 40 Ω. Find the current drawn by the primary of the transformer.
For an LCR circuit, the power transferred from the driving source to the driven oscillator is P = I2Z cos φ.
- Here, the power factor cos φ ≥ 0, P ≥ 0.
- The driving force can give no energy to the oscillator (P = 0) in some cases.
- The driving force cannot syphon out (P < 0) the energy out of oscillator.
- The driving force can take away energy out of the oscillator.
Efficiency of transformer is the ratio of ______.
What is a transformer?
