# Kindly pls check my physics answers

1. Apr 5, 2004

### cseet

A circuit breaker is rated for a current of 15 A rms at a voltage of 120 V rms. Answer the following questions:
All answers must have three significant digits unless otherwise specified.

1) What is the largest value of I(max) that the breaker can carry? (Unit: A)

I(max) = 15(rms) / square root of 2
= 10.6A

2) What average power can be supplied by this circuit? (Unit: kW)

P(rms) = I (rms) * V (rms)
= 1.80 kW

pls correct me if I was wrong and pls direct me to the right path...
thanks
cseet

2. Apr 5, 2004

### Chen

Argh, stupid me.

I(max) = 15(rms) / square root of 2 is not correct, it should be:
I(max) = 15(rms) * square root of 2 if I'm not mistaken.

Last edited: Apr 5, 2004
3. Apr 5, 2004

Hi chen,

thanks
cseet

4. Apr 5, 2004

### Chen

Yes, 1.8kW. By the way, you could have noticed that your first answer is wrong because the maximum current cannot be lower than the average current.

5. Apr 5, 2004

### cseet

Thanks Chen... I see that now...
you have a good day
cseet