# Resistance and Power if an element is removed from parallel circuit

#### xllx

1. The problem statement, all variables and given/known data
A heater consists of heating elements connected in parallel across a power supply. A wire in one of the heating elements breaks. What happens to the total resistance of the heater? And the power output of the heater?

3. The attempt at a solution
Will the resistance increase and the power decrease? I'm just not sure how to explain why that happens.

Any help at all would be greatly appreciated! Many Thanks!

#### Doc Al

Mentor
What do you think?

How do resistors in parallel add?

#### Astronuc

Staff Emeritus
What is the value of total resistance for N resistors R in parallel? Then N-1 resistors in parallel?

Then look at P as a function of V and I, and remembering the relationship between V, I, and R.

#### xllx

Will the resistance increase because the Total Resistance=Value of 1 resistor/Number of resistors. So if there is one less resistor then the total resistance will be greater. Is this right??

And for the power, would I use P=V^2/R. Because voltage will stay the same but resistance has increased, therefore making power decrease? Thanks

Mentor
Sounds good!

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