How is the brightness of a light bulb related to resistance?

Answer 1

The brightness of a light bulb is directly related to the amount of current passing through it, which is determined by the resistance of the bulb. In simple terms, the higher the resistance of the bulb, the lower the current passing through it, resulting in lower brightness. This relationship is described by Ohm's Law, which states that the current passing through a conductor (such as a light bulb) is directly proportional to the voltage across it and inversely proportional to its resistance.

Answer 2

To run at the same voltage, a higher wattage incandescent light bulb has a lower resistance than other bulbs having a lower wattage.

Ohm's Law (A = V / R) states that, at a given voltage, the lower the resistance of the bulb's filament is made, then the higher its current flow will be. Higher current means more energy, more heat, and more light.

A higher resistance filament restricts the current flow more, resulting in less current, less heat, and less light.

Because of the Power Law (W = V x A) bulbs designed to take the same wattage when running on different voltages must have higher or lower resistances than one another, dependent on the voltage, so as to get the right amount of current to produce the wattage required.

The symbols shown in the equations above are defined as follows:

V = Voltage (the electrical potential difference, measured in volts)

A = Amperes (the electrical current or charge flow rate, measured in amps which are defined as coulombs per second)

R = Resistance (the electrical resistance to current flow, measured in ohms)

W = Wattage (the electrical power consumed, measured in watts)

Answer 3

The brightness of a light bulb is indirectly related to its resistance. A higher resistance in the bulb will decrease the current passing through it, resulting in lower brightness. Conversely, lower resistance will allow more current to flow, leading to a brighter light output.