Answer:
59
Explanation:
V = Voltage = 180 V
P = Power = 150 W
I = Current = 49 A
Power is given by
[tex]P=\dfrac{V^2}{R}\\\Rightarrow R=\dfrac{V^2}{P}\\\Rightarrow R=\dfrac{180^2}{150}\\\Rightarrow R=216\ \Omega[/tex]
The total resistance
[tex]R_t=\dfrac{V}{I}\\\Rightarrow R_t=\dfrac{180}{49}\\\Rightarrow R_t=3.67346938776\ \Omega[/tex]
The circuit breaker will trip when total resistance drops below 3.67346938776 Ω
The number of lightbulbs is
[tex]n=\dfrac{R}{R_t}\\\Rightarrow n=\dfrac{216}{\dfrac{180}{49}}\\\Rightarrow n=58.8[/tex]
The number of light bulbs is 59 to trip the circuit breaker.
