Question

Household circuits are generally wired in parallel. In a kitchen, a 1230-W toaster, a 310-W blender, and a 70-W lamp are all plugged into the same outlet. Assume that this is a standard outlet with 120 volts across it.What is the total current drawn by the three devices if they are all in use simultaneously.

What is the equivalent resistance of the toaster, blender, and lamp in parallel?

Answer 1

here,

P1 = 1230 W , let the current in toaster be I1

P1 = V * I1

1230 = 120 * I1

I1 = 10.25 A

P2 = 310 W , let the current in blender be I2

P2 = V * I2

310 = 120 * I2

I2 = 2.58 A

P3 = 70 W , let the current in lamp be I3

P3 = V * I3

70 = 120 * I3

I3 = 0.58 A

the total current drawn by the three devices if they are all in use simultaneously , I = I1 + I2 + I3

I = 13.4 A

the equivalent resistance of the toaster, blender, and lamp in parallel , R = V/I = 8.95 ohm