A circuit with a voltage source of 18V, has 3 resistors all connected on parallel, values at 2ohms, 6ohms and 7.5ohms. Find the total circuit resistance, and then subsequently, the total current supplied and power dissipated in the curcuit.

The total resistance is found by the addition of resistors in parallel, in the equation (1/RT)=(1/R1)+(1/R2)+(1/R3), therefore the total resistance is 1.25ohms. Therefore the current is simply IT=VS/RT, which gives us a current of 14.4A, and using P=IxV, the power dissipated is 259.2W.

HM

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