Advertisements
Advertisements
Question
How are the e.m.f in the primary and secondary coils of a transformer related with the number of turns in these coils?
Advertisements
Solution
`"E"_"s"/"E"_"p" = "N"_"s"/"N"_"p"` = turns ratio n
where, s stands for secondary and p stands for primary.
i.e. `"E.M.f. in secondary coil"/"E.m.f. in primary coil" = "Number of turns in primary coil"/"Number of turns in secondary coil"`
APPEARS IN
RELATED QUESTIONS
Explain the significance of Lenz’s law to show the conservation of energy in electromagnetic induction.
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.
In a transformer, the frequency of A.C. voltage ______.
Describe briefly and two energy losses, giving the reasons for their occurrence in actual transformers ?
A transformer lowers e.m.f. 220 V to 12 volts. If the number of turns in primary are 8800, how many turns are in secondary coil?
A transformer lowers e.m.f. from 220 V to 15 V. If 400 W power is given in primary, calculate (i) the current in primary coil and (ii) the current in secondary coil.
Explain the working of the transformer.
Which among the following, is not a cause for power loss in a transformer?
The line that draws power supply to your house from street has ______.
- zero average current.
- 220 V average voltage.
- voltage and current out of phase by 90°.
- voltage and current possibly differing in phase `phi` such that `|phi| < pi/2`.
