Question

Троллебус массой 11т движется равномерно со скоростью 36км/ч.Найти силу тока в обмотке двигателя,если напряжение равно 550В и КПД равен 80%.Коэффициент сопротивления движению равен 0,02.

Answer 1

Так как движение равномерное, Fтяги = Fтрения = kmg

Тогда полезная мощность:

Pпол = Fтяги*v.

Затраченная мощность:

Pзатр = U*I

к.п.д. = (Pпол/Pзатр )*100%

Отсюда: I = Pпол*100/(к.п.д.)*U = 100kmgv/550*80 = 2*11*10^4*10/550*80 = 50A

Ответ: 50 А.

Answer 2

Calculation of Current in the Motor Winding

To calculate the current in the motor winding of the trolleybus, we can use the formula:

Current (I) = Power (P) / Voltage (V)

The power can be calculated using the formula:

Power (P) = Force (F) * Velocity (V)

The force can be calculated using the formula:

Force (F) = Mass (m) * Acceleration (a)

Since the trolleybus is moving at a constant velocity, the acceleration is zero. Therefore, the force can be calculated as:

Force (F) = Mass (m) * Acceleration (a) = 11,000 kg * 0 = 0 N

Now, we can calculate the power:

Power (P) = Force (F) * Velocity (V) = 0 N * 36 km/h = 0 W

Given that the efficiency (η) of the motor is 80%, we can calculate the actual power consumed by the motor:

Actual Power (P_actual) = Power (P) * Efficiency (η) = 0 W * 0.8 = 0 W

Finally, we can calculate the current in the motor winding using Ohm's Law:

Current (I) = Actual Power (P_actual) / Voltage (V) = 0 W / 550 V = 0 A

Therefore, the current in the motor winding of the trolleybus is 0 A.