The two electric bulbs of same power are connected in parallel circuit. If one bulb is glowing and then another bulb is switched on, then brightness of the first bulb increases, decreases or remians unchanged. Expalin.

Explanation

When two bulbs have same power, then their resistance is also same. When second bulb connected in parallel to first bulb is switched on, the effective resistance of circuit becomes half and current in circuit becomes double. Due to it, this double current divides itself equally in two bulbs. So the current in the first bulb remains unchaged. Due to it, the brightness of this bulb remins unchanged.