Maths-
General
Easy
Question
In a hall there are 10 bulbs and their 10 buttons. In how many ways this hall can be enlightened?
- 102
- 1023
- 210
- 10!
The correct answer is: 1023
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A step up transformer connected to a 
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A short solenoid of length 4 cm, radius 2 cm and 100 turns is placed inside and on the axis of a long solenoid of length 80 cm and 1500 turns. A current of 3 A flows through the short solenoid. The mutual inductance of two solenoids is
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Physics-General
