- AVariable resistor
- BRheostat
- CCircular coil
- DBoth a and b
Explanation:
It is rheostat

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Dynamo is a device for converting
|
(a) Electrical energy into mechanical energy |
|
(b) Mechanical energy into electrical energy |
|
(c) Chemical energy into mechanical energy |
|
(d) Mechanical energy into chemical energy |
An ammeter, suspected to give inaccurate reading, is connected in series with a silver voltameter. The ammeter indicates 0.54 A. A steady current passed for one hour deposits 2.0124 gm of silver. If the E.C.E. of silver is 1.118
, then the error in ammeter reading is
|
(a) + 0.04 A |
(b) + 0.02 A |
(c) – 0.03 A |
(d) – 0.01 A |

An oscillator is nothing but an amplifier with
|
(a) Positive feed back |
(b) Large gain |
|
(c) No feedback |
(d) Negative feedback |
The expression for the capacity of the capacitor formed by compound dielectric placed between the plates of a parallel plate capacitor as shown in figure, will be (area of plate = A)
|
(a) |
(b) |
(c) |
(d) |