Two itmes pluged into wall with 15 A breaker

[barthayn]

Homework Statement

You are trying to quickly make breakfast for school. You plug a cofee maker which uses 1200 W into a plug and then plug a toaster of 1800 W into the same electrical outlet. Will the circuit be able to make the load if the circuit breaker is rated 15 A?

W₁ = 1200 W
W₂ = 1800 W
Circuit Breaker = 15 A

Homework Equations

P = VI
R = V/I

The Attempt at a Solution

P = I (W₁+W₂)
P = I (1200 W + 1800 W)
P = I (3000 W)


After that I have no idea what to do. I understand that I need to isolate for A but cannot figure out how. How do I do this? If it is greater than 15 A the breaker will go out correct?

 

[gneill]

Homework Statement

You are trying to quickly make breakfast for school. You plug a cofee maker which uses 1200 W into a plug and then plug a toaster of 1800 W into the same electrical outlet. Will the circuit be able to make the load if the circuit breaker is rated 15 A?

W₁ = 1200 W
W₂ = 1800 W
Circuit Breaker = 15 A

Homework Equations

P = VI
R = V/I

The Attempt at a Solution

P = I (W₁+W₂)
P = I (1200 W + 1800 W)
P = I (3000 W)


After that I have no idea what to do. I understand that I need to isolate for A but cannot figure out how. How do I do this? If it is greater than 15 A the breaker will go out correct?

Your W values are in watts, not volts, so why are you plugging them in as voltages in the P = V*I equation?

Why not try to determine what the maximum number of watts a 15A circuit can supply, then check to see if both appliances together exceed this?

Hint: You'll need to know something else about the power supplied by a plug. Do you know what that might be?

 

[Adjuster]

You already know that P = VI, also that P = 3000W. Hence VI = 3000W, or I = ?

Another hint: you might get a different answer in London than you would in New York!