Question

(a) When does a fuse cut off current? How does it do it?
(b) What is the maximum number of 60 W bulbs that can be run from the mains supply off 220 volts if you do not want to overload a 5 A fuse?

Answer 1

Explanation:

When the current exceeds a safe value which is maybe due to short circuit or overloading, then the fuse cut off the current. And when slowly the current becomes larger, the heat released by it heats up the fuse wire too much. As a result, the wire melts out and breaks the circuit since the fuse wire’s melting point is low. Hence, the circuit’s current is cut off.

(b) Let the number of bulbs that can be run from the mains supply be x.

Power used for x number of bulbs, P = 60x.

According to the question, V = 220V and I = 5A.

As we know, P = VI

       60x = $220V\times5A$

        $x = \frac{1100}{60}$

      = 18.33 ≅ 18 bulbs.

Therefore, a maximum of 18 bulbs of 60 W can be run.

You can get all the answers of Chapter 2 in the link below:

https://brainly.in/question/14961525

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Answer 2

Answer:

this is your ans.

I hope it helps you