- The resistance of the bulb filament can be calculated from its rated power (P) and voltage (V) using the formula P = V²/R. Thus, R = V²/P. - For the given bulb, R = (200 V)² / 50 W = 40000 / 50 = 800 ohms. - When the bulb is connected across a 100 V supply, the power consumed (P') is calculated using P' = V'²/R, where V' = 100 V. - P' = (100 V)² / 800 ohms = 10000 / 800 = 100 / 8 = 12.5 W.
An electric bulb marked as 50 W-200 V is connected across a 100 V supply. The present power of the bulb is
Asked in WBCS Main Paper 4 2019 · Topic: Electric Current (Electrical Power and Energy, Joule heating effect)
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