Question

Вольтметр,включенный параллельно участку цепи с сопротивлением 10 Ом, показал напряжение 5 В. Определить мощность потребляемую данным участком цепи и работу , совершаемую за 10 мин.

Answer 1

Вольтметр фиксирует напряжение U = 5В на концах проводника с сопротивлением r = 10 Ом. Таким образом, мощность, рассеиваемая на проводнике есть
W = UI = U*(U/r) = U²/r = 25/10 = 2.5 Вт
Работа, произведённая за промежуток времени t = 10 мин = 600 сек связана с мощностью след образом (мощность - это СКОРОСТЬ производства РАБОТЫ):
A = Wt = U²t/r = 2.5*600 = 1500 Дж

Answer 2

Calculation of Power and Work

To determine the power consumed by the circuit and the work done over a period of 10 minutes, we need to use the given information: the voltage measured by the voltmeter (5 V) and the resistance of the circuit (10 Ω).

The power consumed by a circuit can be calculated using the formula:

Power (P) = (Voltage (V))^2 / Resistance (R)

Substituting the given values into the formula:

Power (P) = (5 V)^2 / 10 Ω

Simplifying the equation:

Power (P) = 25 / 10 = 2.5 Watts

Therefore, the power consumed by the circuit is 2.5 Watts.

To calculate the work done by the circuit over a period of 10 minutes, we need to use the formula:

Work (W) = Power (P) * Time (t)

Substituting the given values into the formula:

Work (W) = 2.5 Watts * 10 minutes

Since the unit of power is Watts and the unit of time is minutes, the work done will be in Watt-minutes.

Therefore, the work done by the circuit over a period of 10 minutes is 25 Watt-minutes.

Conclusion

The circuit with a resistance of 10 Ω and a voltage of 5 V consumes 2.5 Watts of power and performs 25 Watt-minutes of work over a period of 10 minutes.