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The mains supply in India has a frequency of 50 Hz…
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
The mains supply in India has a frequency of . How many times does the current change its direction in one minute, and in one hour? How long is one cycle, in milliseconds?
Need a reminder? The key ideaShow
A generator turns a coil in a magnetic field. With slip rings it gives alternating current (AC), which changes direction twice in every turn; with a split ring it gives a pulsing direct current (DC). Frequency = turns each second, in hertz; one cycle takes .
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Each second. changes.
Step 2. A minute. changes.
Step 3. An hour. changes.
Step 4. One cycle. .
Answer: in a minute, in an hour, and for a cycle.
Check. A lamp on the mains dims and brightens times a second, too fast for the eye to see.
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