Advertisements
Advertisements
प्रश्न
Draw a neat diagram of an AC generator and explain its working.
Advertisements
उत्तर
An alternating current (AC) generator, consists of a rotating rectangular coil ABCD called armature placed between the two poles of a permanent magnet. The two ends of this coil are connected to the two slip rings S1 and S2. The inner sides of these rings are insulated. Two conducting stationary brushes B1 and B2 are kept separately on the rings S1 and S2 respectively. The two rings S1 and S2 are internally attached to an axle. The axle may be mechanically rotated from outside to rotate the coil inside the magnetic field. Outer ends of the two brushes are connected to the external circuit.
When the coil is rotated, the magnetic flux linked with the coil changes. This change in magnetic flux will lead to generation of induced current. The direction of the induced current, as given by Fleming’s Right Fland Rule, is along ABCD in the coil and in the outer circuit it flows from B2 to B1. During the second half of rotation, the direction of current is along DCBA in the coil and in the outer circuit it flows from B1 to B7. As the rotation of the coil continues, the induced current in the external circuit is changing its direction for every half a rotation of the coil.
APPEARS IN
संबंधित प्रश्न
State the principle of an electric generator.
Name the phenomenon which is made use of in an electric generator.
What type of generator is used at Power Stations?
Explain the principle of an electric generator.
State two ways in the which the current alternating current and direct current?
Draw the labelled diagram of an A.C. generator. With the help of this diagram, explain the construction and working of an A.C. generator.
In an a.c. generator the speed at which the coil rotates is doubled. How would this affect
- the frequency of output voltage,
- the maximum output voltage is doubled.
State one advantage of using a.c. over d.c.
The given figures 1 to 3 show the working of a simple A.C. generator. Study the diagrams and answers of the following questions.
(i) State and explain the principle underlying the working of a simple generator.
(ii) Where is the loop of wire placed?
(iii) What happens when the loop is rotated?
(iv) Indicate the direction of the current flow through the wire for the first half of the turn (in first figure). Name and state the rule used in finding the direction of the current.
(v) Indicate the direction of the current for the case shown in second figure.
(vi) Indicate the direction of current in the outer circuit (i.e., electric bulb) in first and third figure.
(vii) What type of current is shown in the above diagrams? Explain.
A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is withdrawn from inside the coil?
