Will fan and medal:D
Three 9W -3 V bulbs is to be lighted by a suppy of 12 Volt.For this,a wire is to be connected in series with it.Th resistance of the wire should be:
A) 1
B) 2
C) 3
D) 4
Please explain it step by step

Question

Will fan and medal:D
Three 9W -3 V bulbs is to be lighted by a suppy of 12 Volt.For this,a wire is to be connected in series with it.Th resistance of the wire should be:
A) 1
B) 2
C) 3
D) 4
Please explain it step by step

vijeya · Answer

@phi

vijeya · Answer

@ganeshie8

vijeya · Answer

@Abhisar

vijeya · Answer

@imqwerty

ganeshie8 · Answer

Each bulb is rated at 9W
So what current must flow in order for the voltage to be 3V across each bulb ?

vijeya · Answer

i am not sure:(

ganeshie8 · Answer

use this : 

power = voltage * current

ganeshie8 · Answer

you're given power = 9W and voltage = 3V

plug them in and find the current

vijeya · Answer

oh yeah!i didn't think of that!
that would be 3A

ganeshie8 · Answer

Yes, so 3A must flow in the circuit

vijeya · Answer

u mean that would be all to this question?

ganeshie8 · Answer

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