Advertisements
Advertisements
Question
On which type of current do transformers work?
Advertisements
Solution 1
The transformer works on alternating current or A.C. current.
Solution 2
No, they aren't suitable for use with direct current because, in the absence of a change in the magnetic field lines connected to the coils, no induced current can flow in the other coil.
APPEARS IN
RELATED QUESTIONS
Draw a labeled diagram of a step-down transformer.
State the principle of the step-down transformer and its working.
Why is the core of a transformer laminated?
The adjacent diagram shows a coil would around a soft iron bar XY. (a) State the polarity at the end X and Y as the switch is pressed. (b) Suggest one way increasing the strength of electromagnet so formed.

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.
State the underlying principle of a transformer. How is the large scale transmission of electric energy over long distances done with the use of transformers?
Distinguish between Step up and Step Down Transformer.
Mention the various energy losses in a transformer.
Read the following paragraph and answer the question:

Long distance power transmissions
The large-scale transmission and distribution of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped up. It is then transmitted over long distances to an area sub-station near the consumers. There the voltage is stepped down. It is further stepped down at distributing sub-stations and utility poles before a power supply of 240 V reaches our homes.
We need to step-up the voltage for power transmission, so that ______.
In an ideal transformer, the turns ratio is `N_p/N_s = 1/2`. The ratio Vs : Vp is equal to (the symbols carry their usual meaning):
