Answer:
The current supplies the maximum wattage is 6 Ampere.
Step-by-step explanation:
Given : In a 120-volt circuit having a resistance of 10 ohms, the power W in watts when a current I is flowing through is given by [tex]W=120I-10I^2[/tex]
To find : What current supplies the maximum wattage?
Solution :
The equation of power is
[tex]W=120I-10I^2[/tex]
Derivate w.r.t x,
[tex]W'=120-20I[/tex]
For critical point put it to zero,
[tex]120-20I=0[/tex]
[tex]20I=120[/tex]
[tex]I=\frac{120}{20}[/tex]
[tex]I=6[/tex]
Now, again derivate w.r.t I,
[tex]W''=-24<0[/tex]
It is maximum at I=6 A
Therefore, the current supplies the maximum wattage is 6 Ampere.
