A light bulb glows because it has resistance. The brightness of a light bulb increases with the electrical power dissipated in the bulb, (a) In the circuit shown in Fig. Q25.14a, the two bulbs A and B are identical. Compared to bulb A, does bulb B glow more brightly, just as brightly, or less brightly? Explain your reasoning, (b) Bulb B is removed from the circuit and the circuit is completed as shown in Fig. Q25.l4b. Compared to the brightness of bulb A in Fig. Q25.l4a, does bulb A now glow more brightly, just as brightly, or less brightly? Explain your reasoning.
Figure Q25.14
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