Final answer:
The resistance of a 75-W lightbulb connected to 110 V is approximately 161.33 ohms and the current is about 0.682 A. For a 250-W lightbulb, the resistance is around 48.4 ohms, with a current of approximately 2.273 A.
Step-by-step explanation:
Part A: Resistance of a 75-W Lightbulb
To determine the resistance of a 75-W lightbulb connected to a 110 V source, use the power formula P = V^2 / R, where P is power, V is voltage, and R is resistance. R = V^2 / P, thus R = (110 V)^2 / 75 W, which calculates to approximately 161.33 ohms.
Part B: Current through a 75-W Lightbulb
The current through a lightbulb can be calculated by the power formula P = IV, where P is power, I is current, and V is voltage. I = P / V, so I = 75 W / 110 V, which results in approximately 0.682 A.
Part C: Resistance of a 250-W Lightbulb
In the case of the 250-W lightbulb, using the formula R = V^2 / P, R = (110 V)^2 / 250 W gives a resistance of approximately 48.4 ohms.
Part D: Current through a 250-W Lightbulb
Using I = P / V for the 250-W lightbulb, I = 250 W / 110 V, the current through the bulb is approximately 2.273 A.