Advertisements
Advertisements
प्रश्न
The primary coil of an ideal step-up transformer has 100 turns and the transformation ratio is also 100. The input voltage and power are 220 V and 1100 W, respectively. Calculate the
(a) number of turns in secondary
(b) current in the primary
(c) a voltage across secondary
(d) current in secondary
(e) power in secondary
Advertisements
उत्तर
(a) Number of turns in secondary coil is given by
`N_S/N_P=n`
`=>N_S/100=100`
⇒NS=10,000
(b) Current in primary is given by
IPVP=P
`=>I_P=1100/220=5A`
(c) Voltage across secondary is given by
`V_S/V_P=N_S/N_P=n`
⇒VS=100×220=22,000 V
(d) Current in secondary is given by
VSIS=P
`=>I_S=P/V_S=1100/22000=0.05A`
(e) Power in secondary is power in primary in an ideal transformer.
= 1,100 W
संबंधित प्रश्न
On which type of current do transformers work?
The transformer is used in ______ current circuits.
Draw a labeled diagram of a full wave rectifier circuit. State its working principle. Show the input-output waveforms ?
The power supply to the primary coil of a transformer is 200 W. Find
(i) Current in primary coil if the e.m.f. supply to it is equal to 220V.
(ii) The number of turns in the primary coil is equal to 80 and that in secondary is 800. What is the transformation ratio?
(iii) Name the type of transformer.
(iv) What will be the output voltage?
(v) What is the current in the secondary coil for an ideal transformer?
(vi) What is the output power?
(vii) Is output and input power equal?
(viii) Compare the current flowing in a secondary coil and in a primary coil.
The primary coil of a transformer has 200 turns while the secondary coil has 1000 turns. What type of transformer is this? if the input voltage is 10V, what will be the output voltage?
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.
Assertion: A transfonner cannot work on D.C. supply.
Reason: D.C. changes neither in magnitude nor in direction.
A step-down transformer connected to an ac mains supply of 220 V is made to operate at 11 V, 44 W lamp. Ignoring power losses in the transformer, what is the current in the primary circuit?
A transformer operating at primary voltage 8 kV and secondary voltage 160 V serves a load of 80 kW. Assuming the transformer to be ideal with purely resistive load and working on unity power factor, the loads in the primary and secondary circuit would be:
For what purpose are the transformers used?
