Question

Three 2 Ω resistors, A, B and C, are connected as shown in Figure. Each of them dissipates energy and can withstand a maximum power of 18 W without melting. Find the maximum current that can flow through the three resistors?

Answer 1

P = I²R
where, 
P = Potential difference
I = Current
R = Resistance 

For resistor A,
18 = I² × 2

`"I"^2= 18/2`

I² = 9

I = 3A

This is the maximum current that can flow through the resistor A. 

The maximum current flowing through the resistors B and C, `"I"^"'"=3×1/2 = 1.5  "A"`