What is the resistance value of a resistor when a voltage of 10V is applied at its two ends and the current is 0.5A?

What is the resistance value of a resistor when a voltage of 10V is applied at its two ends and the current is 0.5A?

20 ohm, divide the voltage by the current, if it is pure resistance. If it is not pure resistance, the condition is insufficient and cannot be calculated

As shown in the figure, the power supply consists of two new dry batteries, with resistance R = 20 Ω and lamp L marked with "6V & nbsp; 3.6W". After closing switch s, the current in the series circuit is______ A. The power consumed by lamp L is______ W．

(1) The resistance of the bulb RL = u2lpl = (6V) 23.6w = 10 Ω, so the current in the circuit I = ur + RL = 3v20 Ω + 10 Ω = 0.1A. Answer: the current in the circuit is 0.1A. (2) the power consumed by lamp L p = i2rl = (0.1A) 2 × 10 Ω = 0.1W. Answer: the power consumed by lamp L is 0.1W

The rated power of the small bulb is 1.8W, and the rated voltage is less than 8V. When it is connected in parallel with a 30 ohm resistor, the main circuit current is 0.5A, and the bulb lights normally, calculate the rated voltage and other resistance value of the small bulb

If I = u / R is used to represent the current of each branch: IO = u / Ro, IL = u / RL; then there is equation 1: U / Ro + U / RL = I = 0.5A; P = u & # 178 / R is obtained from P = UI and I = u / R; R is the rated power of the bulb (equation 2): U & # 178 / RL = PL = 1.8W

In the circuit shown in Figure 15-45, the resistance RL of lamp L is 40 Ω, R is a rheostat marked with "20 Ω, 1.5A", and the power supply is a battery pack composed of two dry batteries in series. Try to find the change range of ammeter and voltmeter

The current: 3V / (40 + 0) = 0.075a, 3V / (40 + 20) = 0.05A. (voltage divided by resistance = current) the current varies between 0.05-0.075a. The voltage at both ends of the lamp: when the rheostat is 0 ohm, the voltage of the lamp is 3V (the power supply voltage is all applied to the lamp)