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Rated at 100 v. can a 10 W power supply guarantee the proper operation of a 2K ohm resistor rated at 100 V?
The rated power of 100V 2K resistor is: P = u △ r = 100 △ 2000 = 5 W ＜ 10 W, then the power supply can drive the load completely
If a 10 ohm resistor is connected to a 3-volt power supply, the current through the resistor is I. If a 30 ohm resistor is connected to the same power supply, the current through the resistor is I
I30 = I * 10 / (10 + 30) a on a 30 ohm resistor
According to Ohm's law, I = u / R, the voltage is constant, the current is inversely proportional to the resistance, and the 30 ohm resistance is three times of the 10 ohm resistance, so the current on it is 1 / 3 of the 10 ohm resistance current I
When a 50 ohm resistor is connected to a current, the current passing through the resistor is 0.1A; when a 10 ohm resistor is connected to the same power supply, the current passing through it is 0.1A
U = I * r = 50 Ω * 0.1A = 5V
I = u / r = 5V / 10 Ω = 0.5A
A: its current is 0.5 a
There is a small motor with a resistance of 10 ohm and a rated voltage of 6 v. there is a power supply with a voltage of 9 v. what should we do to make the motor work normally
calculation
The rated current of small motor in normal operation is: I = 6V / 10 Ω = 0.6A
9V is 3V higher, so a resistor should be connected in series to separate 3V. The value of this resistor is: r = 3V / 0.6A = 5 Ω
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