I have a 5W lamp on 12Volts battery, I want it to be half as bright, so I will add a resistor. What resistor should I supply?
A = W = 5 = 0.416mA
_ _
V 12
R = V = 12 = 28.84 Ohms (R) this is resistance of lamp
_ _____
I 0.416
So I will add one resistor 28.84 Ohms
I will have 28.84 + 28.84 = 57.6 Ohms
Or 28.84 + 28.84 = 14.42 Ohms
I don't know if it will work in series or in parallel
voltage would be 6V and amp current mA = 0.208mA We divide everything by two
W= V * I = 6 * 0.208 = 1.248Watts resistor would be needed and 28.84 Ohms
Is my calculation correct? And I need explanation why its divided by two I'm little confused
A = W = 5 = 0.416mA
_ _
V 12
R = V = 12 = 28.84 Ohms (R) this is resistance of lamp
_ _____
I 0.416
So I will add one resistor 28.84 Ohms
I will have 28.84 + 28.84 = 57.6 Ohms
Or 28.84 + 28.84 = 14.42 Ohms
I don't know if it will work in series or in parallel
voltage would be 6V and amp current mA = 0.208mA We divide everything by two
W= V * I = 6 * 0.208 = 1.248Watts resistor would be needed and 28.84 Ohms
Is my calculation correct? And I need explanation why its divided by two I'm little confused
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