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Question Raghu is fond of his grandfather’s torch. He starts playing with it. He presses the switch once and the light turns ON. He presses it a second time and the light turns OFF. He presses the switch a third time and the light turns ON. He keeps doing this several times. Will the torch be ON or OFF after the 23rd press? How do you know?
For what number of presses will the torch be ON? For what number of presses of the switch will the torch be OFF?
Raghu presses the switch again and again.
Every time he presses it, the torch changes its state. Let see the pattern:
1st Press → Torch turns ON
2nd Press → Torch turns OFF
3rd Press → Torch turns ON
4th Press → Torch turns OFF
and so on…
We observe that: After an odd-numbered press the Torch is ON and after an even- numbered press the Torch is OFF.
Since 23 is an odd number, so torch will be ON after the 23rd press.