Question

1до кінців провідника подають деяку різницю потенціалів.як змінеться сила струму в провіднику,якщо його довжину зменшити вдвічі? 2визначте потужність електричної лампи ,опір якої500 ом ,якщо вона працює при напрузі 200В.

Answer 1

1.зменшиться в двічі
2. 80Вт

Answer 2

Effect of Halving the Length of a Conductor on Current

When the length of a conductor is halved, the resistance of the conductor remains the same, assuming the material and cross-sectional area of the conductor remain constant. According to Ohm's Law, the current flowing through a conductor is inversely proportional to its resistance. Therefore, if the resistance remains the same and the potential difference across the conductor remains the same, the current flowing through the conductor will also remain the same.

Calculation of Power for an Electric Lamp

To calculate the power of an electric lamp, we can use the formula: Power (P) = (Voltage (V))^2 / Resistance (R). Given that the resistance of the lamp is 500 ohms and the voltage is 200V, we can substitute these values into the formula to find the power.

P = (200V)^2 / 500 ohms

Simplifying the equation:

P = 40000V^2 / 500 ohms

P = 80V^2 ohms

Therefore, the power of the electric lamp is 80V^2 ohms.