Efficiency of a 265W motor drawing 4.30A from 120V line

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aMo0oDi
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What is the efficiency of a 265W motor that draws 4.30A from 120V line?
How much energy in Joules does this motor use in 1.50 hour?

thanks in advance..
 
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power has two equations :
1) P(t)= W/t = -PE/t = q.V/t = I.V
2) P= I (I.R)
 
aMo0oDi said:
power has two equations :
1) P(t)= W/t = -PE/t = q.V/t = I.V
2) P= I (I.R)

Power can also be expressed as P=V^2/R

Now what is efficiency defined as?

Finally, what information are you given and what can you do with it?
 
aMo0oDi said:
power has two equations :
1) P(t)= W/t = -PE/t = q.V/t = I.V
2) P= I (I.R)
If W/t=IV
W=J/s
I=Amps
V=Volts

You just plug it in, then find the efficiency.