JAMB - Physics (1995 - No. 45)
The fig above shows two similar bulbs X and Y connected to suitable power supply with F as an appropriate fuse rating, if the filament of X breaks then the
Brightness Of Y will reduce
Brightness Of Y will remain constant
Brightness Of Y will increase
fuse F will blow
คำอธิบาย
Diagram above shows a Parallel circuit
If one of the parallel path is broken, current will continue to flow in other parts.
Voltage is the same across each component of the parallel circuit.
The brightness of a light bulb is given by its power. P = I\(^2\)R,
and so brightness depends on current and resistance.
Hence; the brightness of Y will not be affected except for a variation in resistance property.