the current through a 12v tungsten filament lamp connected to a 12v battery of negligible resistance is 3A. Calculate (i) the resistance of the filament (ii)power of the lamp and (iii) the electrical energy consumed in 5 hrs

pls. i need the answer immediatly

Given, I = 3 A
V = 12 Volts
(i) Using Ohm's law :
V = I R, where R is the resistance of the filament.
So, R = V/I = 12/3 = 4 ohms
(ii) Since, P = I2 R
So, power of the lamp, P = (3)2 X 4 =  36 Watt
(iii) Electric energy consumed in 5 hours can be calculated by the formula :
E = P X t
given, t = 5 hours = 5 X 3600 = 18000 s
So, E = 36 X 18000 =  648000 joules
 

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