Resistance Of A 12 Volt 21 Watt Bulb

According to ohm s law i v r.

Resistance of a 12 volt 21 watt bulb.

I will assume this a dc application. Technician b says that a motor that has 1 ohm of resistance has a power rating of 144 watts if it is connected to a 12 volt battery. Fields should be reset to 0 before each new calculation. 55 miniature bulb ba9s base 7 0 volt 41 amp 2 87 watt g4 1 2 ba9s base 500 hour 921 w16w miniature bulb glass wedge base 12 8 volt 1 40 amp 17 92 watt t5 glass wedge base 1 000 hour 912 miniature bulb glass wedge base 2826 miniature bulb glass wedge base.

However if i use r volts squared watts 5 watt bulb 28 8 ohms 6 watt bulb 24 ohms 10 watt bulb 14 4 ohms. 12 volts and 21 watts. According to watts law power p i v. Looking in maplin most resistors seem to be designated in watts or ohms watts which has got me really confused.

These differ from the first set by a factor of 10. 21 w 12 v x current. 5 watt bulb 2 9 ohms 6 watt bulb 2 1 ohms 10 watt bulb 1 8 ohms. I am pretty sure my meter is giving me the correct reading and that i am using it correctly.

The resistance of the bulb is 12 v 1 75 a 6 86 ω. Where i current. Current 21 w 12 v 1 75 amps. But in reality the resistance probably will go to infinity as that much current would almost certainly blow the filament.

Voltage e current i resistance r. 2821 w3w miniature bulb glass wedge base 12 volt 0 25 amp 3 watt t3 1 4 miniature wedge base 1 000 hour 1034a amber miniature bulb bay15d base 12 8 14 0 volt 1 80 0 59 amp 23 8 26 watt painted amber s8 dc index bayonet base 200 5000 hour. Technician a says that a 12 volt light bulb that draws 12 amps has a power output of 1 watt. Enter 100 in the watts field and 120 in the voltage field and press calculate to find the resistance and current.

Watts voltage x current. In theory the formula v ir i is current 12 55 or approximately 0 2 ohms. Looking for a resistor to mimic a 12v 21w bulb car with an indicator flasher unit designed for 2 x 21w 5w but only using 1 x 21w 1 x 5w trying to remember my o level physics i worked out that current would be 1 75a and therefore resistance would be roughly 7ohms. V voltage and.