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प्रश्न
State the principle of a step-up transformer. Explain, with the help of a labeled diagram, its working ?
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उत्तर
Transformer:
Principle: It is a device which converts high voltage AC into low voltage AC and vice-versa. It is based upon the principle of mutual induction. When alternating current is passed through a coil, an induced emf is set up in the neighbouring coil.
Working: When an alternating current is passed through the primary, the magnetic flux through the iron core changes, which does two things. It produces emf in the primary and an induced emf is also set up in the secondary. If we assume that the resistance of primary is negligible, then the back emf will be equal to the voltage applied to the primary.
`therefore V_1 = -N_1 (dphi)/(dt)`
and`,V_2 = -N_2 (dphi)/dt`
Where, N1 and N2 are number of turns in the primary and the secondary respectively and V1 and V2 are their voltages respectively
In a step-up transformer: N2 > N1, therefore, V2 > V1
संबंधित प्रश्न
Find the ratio of primary and secondary currents in terms of turn ratio in an ideal transformer.
On which type of current do transformers work?
The following diagram in Fig. 10.44 shows a coil X connected to a sensitive centre –zero galvanometer G and a coil P connected to a battery through a switch S.
(a) Describe the observation when the switch S is (i) closed suddenly, (ii) then kept closed, (iii) finally opened.
(b) Name and state the law which explains the above observations.
The secondary windings of a transformer in which the voltage is stepped down are usually made of thicker wire than the primary. Explain why.
The input and output voltages of a transformer are 220 V and 44V respectively. Find the current in input circuit if the output current is 2 A.
A step-down transformer reduces the supply voltage from 220 V to 11 V and increase the current from 6 A to 100 A. Then its efficiency is
Which among the following, is not a cause for power loss in a transformer?
Define a Transformer.
The primary winding of a transformer has 100 turns and its secondary winding has 200 turns. The primary is connected to an a.c supply of 120 V and the current flowing in its is 10 A. The voltage and the current in the secondary are ______.
