A locomotive train is experiencing a frictional resistance when traveling at 20m/s and the resistance is 1500N. The power development by its engine is 200kW

Calculate
a) The output power of the train
b) the efficiency of the train

1 answer

a) To calculate the output power of the train, we first need to determine the total resistance the train is facing at 20m/s. This can be done using the formula:

Total resistance = Frictional resistance + Air resistance

Given that the frictional resistance is 1500N and the air resistance is not provided, we will assume the air resistance to be negligible for the calculation.

Total resistance = 1500N

Next, we can calculate the output power of the train using the formula:

Output power = Force x Velocity

Output power = Total resistance x Velocity

Output power = 1500N x 20m/s

Output power = 30000 watts

Convert watts to kilowatts:

Output power = 30000 watts = 30 kW

Therefore, the output power of the train is 30 kW.

b) The efficiency of the train can be calculated using the formula:

Efficiency = (Output power / Input power) x 100%

Given that the input power is 200 kW, we can substitute the values into the formula:

Efficiency = (30 kW / 200 kW) x 100%

Efficiency = 0.15 x 100%

Efficiency = 15%

Therefore, the efficiency of the train is 15%.