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How much resistance does it take to connect 1 LED (light emitting diode) in series with 24 V voltage
If DC24 V, 1K is OK, and it's still relatively bright. The fault light on our equipment is 1K resistor in series and 1 / 8W carbon film resistor
220 voltage series 71 green LED beads to use resistance? With how much resistance?
DC 220 V
With a resistance of 400 Ω and 5W, you can determine that the voltage is dc220v
The actual power of the bulb is determined by the actual voltage at both ends of the bulb. Then, is the actual power of the bulb determined by the actual current of the bulb?
The two statements are the same, because u = IR, and R is constant
If a small bulb marked "6V 3W" is connected to a circuit with a voltage of 4V, how much work does the current do in 10min
Resistance of small bulb: r = u & # 178 / P = 6 & # 178 / 3 = 12 (Ω)
When the small bulb is connected to the circuit with voltage of 4V, the work done in 10min is as follows:
W=U'²t/R=4²×（10×60）/12=800(J)
A: slightly
If there is a small light bulb in a circuit and there is a charge of 150C passing through within 10min, the current passing through the small light bulb is (). How to calculate?
Formula?
I=Q/t=15/60A=0.25A
U=I*R=0.25*12V=3V
The definition of current is the charge passing through the unit time (the current is represented by the letter I, the time is represented by T, and the charge is represented by Q)
So t = 10min = 600s
The current is I = q / T = 150C / 600s = 0.25A
And you give u = I * r = 0.25 * 12V = 3V (u for voltage, R for resistance)
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