Ohm's law
Ohm’s law is a prominent concept in physics and electronics. It gives the relation between the current and the voltage. It is used to analyze and construct electrical circuits. Ohm's law states that the voltage across a conductor is directly proportional to the current flowing through it.
Path of Least Resistance
In a series of alternate pathways, the direction of least resistance is the actual or metaphorical route that offers the least resistance to forwarding motion by a given individual or body.
Light bulbs are often assumed to obey Ohm's law. However, this is not really true because their resistance increases substantially as the filament heats up in its "working" state.
A typical flashlight bulb at full brilliance draws a current of approximately 0.5 A when connected to a 3-V voltage source. For this problem, assume that the changing resistance causes the current to be 0.5 A for any voltage between 2 and 3 V.
Suppose this flashlight bulb is attached to a capacitor as shown in the circuit from the problem introduction. If the capacitor has a capacitance of 3 F (an unusually large but not unrealistic value) and is initially charged to 3 V how long will it take for the voltage across the flashlight bulb to drop to 2 V (where the bulb will be orange and dim)? Call this time tbright.
Express tbright numerically in seconds to the nearest integer.
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