What happens to the brightness of light emitted by a light bulb when the current in the filament increases?
The brightness increases.
When the current in the filament of a light bulb increases, the brightness of the light emitted by the bulb also increases. This is because the brightness of a light bulb is directly proportional to the amount of electrical power it consumes.
To understand why this happens, we need to consider the concept of electric power. Electric power is the rate at which electrical energy is converted into other forms of energy, such as light or heat. It is calculated by multiplying the voltage (V) across a device by the current (I) passing through it, using the formula P = VI (where P is power).
In the case of a light bulb, the filament inside the bulb acts as a resistor, converting electrical energy into light and heat. The filament's resistance remains constant, so when the current passing through the filament increases, the power consumed by the bulb increases as well.
As a result, the filament gets hotter, and more light is emitted. This increase in brightness is a direct result of the increased power flowing through the bulb. Therefore, when the current in the filament of a light bulb increases, the brightness of the light emitted by the bulb also increases.