- AA. C. circuits.
- BD. C. circuits.
- CBoth (a) and (b).
- DNeither (a) nor (b).
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A heater coil is cut into two parts of equal length and one of them is used in the heater. The ratio of the heat produced by this half coil to that by the original coil is
|
(a) 2 : 1 |
(b) 1 : 2 |
(c) 1 : 4 |
(d) 4 : 1 |
A circular coil of mean radius of 7 cm and having 4000 turns is rotated at the rate of 1800 revolutions per minute in the earth's magnetic field (B = 0.5 gauss), the maximum e.m.f. induced in coil will be
|
(a) 1.158 V |
(b) 0.58 V |
(c) 0.29 V |
(d) 5.8 V |
In Milikan's oil drop experiment, a charged drop falls with terminal velocity V. If an electric field E is applied in vertically upward direction then it starts moving in upward direction with terminal velocity 2V. If magnitude of electric field is decreased to
, then terminal velocity will become
|
(a) |
(b) V |
(c) |
(d) 2V |
Three identical capacitors are given a charge Q each and they are then allowed to discharge through resistance R1, R2 and R3. Their charges, as a function of time shown in the graph below. The smallest of the three resistance is

|
(a) R3 |
(b) R2 |
(c) R1 |
(d) Cannot be predicted |
A coil of wire of a certain radius has 600 turns and a self inductance of 108 mH. The self inductance of a 2nd similar coil of 500 turns will be
|
(a) 74 mH |
(b) 75 mH |
(c) 76 mH |
(d) 77 mH |
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