Question

Поезд массой 500т,двигаясь прямолинейно,увеличивает свою скорость от 60км\ч до 80км\ч.Какую работу при этом совершают тяги?

Answer 1

500т=500000кг
60 км/ч= 60*1000м/3600с=16,6666м/с=17м/с (округляем)
80 км/ч= 80*1000м/3600с=22,2222м/с=22м/с
V²₁=17²= 289
V²= 22²= 484
A=FS=maS=m(V²-V²₁/2S)*S=m*(V²-V²₁)/2
A= 500000кг(484 - 289)/2=48750000Дж=48,75 МДж
если немного иначе округлить,ответ может немного отличаться. 

Answer 2

Calculation of Work Done by the Train

To calculate the work done by the train, we can use the formula:

Work = Force × Distance

In this case, the force can be calculated using Newton's second law of motion:

Force = Mass × Acceleration

The distance traveled by the train can be calculated using the formula:

Distance = Average Velocity × Time

Let's calculate the work done by the train step by step.

1. Mass of the train: 500 tons (or 500,000 kg). 2. Initial velocity: 60 km/h. 3. Final velocity: 80 km/h. 4. Time taken to increase the velocity: Not provided.

To calculate the work done, we need to know the time taken to increase the velocity. Could you please provide the time taken?