- AOn heating with ac
- BOn heating with de
- ✓Same in both
- DNone of the above two
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A cable of resistance 10 Ω carries electric power from a generator producing 250 kW at 10000 volt. The current in the cable is
|
(a) 25 A |
(b) 250 A
|
(c) 100 A |
(d) 1000 A |
An electron makes a transition from orbit n = 4 to the orbit n = 2 of a hydrogen atom. The wave number of the emitted radiations (R = Rydberg's constant) will be
|
(a) |
(b) |
(c) |
(d) |
A condenser having a capacity of 6mF is charged to 100 V and is then joined to an uncharged condenser of 14 μF and then removed. The ratio of the charges on 6mF and 14mF and the potential of 6mF will be
|
(a) |
(b) |
(c) |
(d) |
A lens behaves as a converging lens in air and a diverging lens in water. The refractive index of the material is
|
(a) Equal to unity |
(b) Equal to 1.33 |
|
(c) Between unity and 1.33 |
(d) Greater than 1.33 |