Bulb 4

In an electric circuit, a bulb (4.5 V, 0.1 A) and a resistor with resistance 45 Ω are connected to a 4.5 V voltage source. Will the bulb shine at full brightness in this circuit? Support your answer with calculations, and possibly look for solutions so that the bulb shines at full brightness. I.e. calculate the power of the bulb (consider the bulb a linear resistor) if it is connected in series and then in parallel with the resistor. .. .

Final Answer:

p₁ =  50 %
p₂ =  100 %

Step-by-step explanation:

$$\begin{gathered} U=4.5\text{V} \\ I=0.1\text{A} \\ R=U/I=4.5/0.1=45\Omega \\ {R}_2=45\Omega \\ {R}_3=R+R_2=45+45=90 \\ {I}_1=U/R_3=4.5/90=\frac{1}{20}=0.05\text{A} \\ {p}_1=100\cdot \frac{I_1}{I}=100\cdot \frac{0.05}{0.1}=50\% \end{gathered}$$

$$\begin{gathered} I_2=I=0.1=\frac{1}{10} \\ {p}_2=100\cdot \frac{I_2}{I}=100\cdot \frac{0.1}{0.1}=100\% \end{gathered}$$

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