Question

do it fast pleasemmmmmm​

Answer 1

Step-by-step explanation:

In this problem we have finite number of bulbs connected in parallel.

The first step is to find the resistance of a single bulb. This resistance can be found from the known values of the power of the bulb and its voltage. The power is 10 W and the voltage is 220 V.

We use the expression for the power of the bulb in terms of the voltage and its resistance

current

We substitute the known values (power and voltage) in the above expression and obtain

potential

Then the resistance is

voltage

This is the resistance of one bulb. Now we connect charge bulbs in parallel (we do not know the exact number of bulbs at this point – this is what we need to find the problem). The equivalent resistance of N bulbs connected in parallel is

electric

Then

problem

Now we know equivalent resistance and we can calculate the current in the circuit. The voltage is 220 V. We apply the Ohm’s law and obtain the current

field

We substitute resistance of one bulb in the above expression and obtain

series

We know that the current should be less than 5 A, then

parallel

And

connection

From this expression we can find N:

junction

Since N is integer, then the maximum number of bulbs is 111.

Answer 2

Step-by-step explanation:

This is the resistance of one bulb. Now we connect charge bulbs in parallel (we do not know the exact number of bulbs at this point – this is what we need to find the problem). The equivalent resistance of N bulbs connected in parallel is

electric

Then

problem

Now we know equivalent resistance and we can calculate the current in the circuit. The voltage is 220 V. We apply the Ohm’s law and obtain the current

field

We substitute resistance of one bulb in the above expression and obtain

series

We know that the current should be less than 5 A, then

parallel

And

connection

From this expression we can find N:

junction

Since N is integer, then the maximum number of bulbs is 111.