# Chapter 1

• W pobliżu

Pociagi potrzebuja 30 minut aby sie zderzyc gdyz pociag A poruszjac sie ze stala predkoscia 160 km/h po 30 minutach pokona 80 km

pociag B poruszajac sie ze stala predkoscia 120 km/h pokona w 30 minut 60 km

80 + 60 = 140

Pracownik poruszajac sie ze stala predkoscia 14 km/h pokona w ciagu 30 minut 7 km a ma pokonac dystan 6300 m czyli po 27 minutach zdazy przelaczyc semafor i uratowac pociagi przed zdarzeniem

• he will make it,

14km/60 => 233,33 m/s

so

6300m he will reach in 27mins

faster train will make 80km in 30mins

slower train will make 60km in 30mins

80+60=140km

trains will meet in 30min

• It will take him 27 minutes (.45 hours) to cover the 6300m. In that time Train A will travel 72 km and Train B will travel 54 leaving them 14 km apart when the itch is thrown.

• Yes he will be in time. Trains will colide in 0,5h 140km/(160+120). Supervisor will run for 0,45h 6,3/14. 0,5h>0,45h

• The trains could collide in half an hour. The supervisor runs at 14,000 metres an hour so will arrive at the switches well within time to stop both trains.
HOWEVER modern signalling, even the old British block signalling system, would not allow this issue to arise.

• Yes, became go to the switch in 27 minutes

• The supervisor runs at 14 km/h.

The swith is at 6.3 km

He needs 0.45 h to reach it (6.3/14 = 0.45)

The distance between the trains is: 140 km

The trains run at 160 km/h and 120 km/h. The are approaching at 280 km/h

They will be in contact in 0.5 h (140 / 280 = 0.5)

The supervisor can switch BEFORE the collision because he needs 0.45 h whereas the collision could happen after (0.5h)

• le régulateur arrivera à temps, les trains vont mettre 1h pour se rejoindre alors que lui sera arrivé en moins d'une demie heure

• yes, he managed to avoid the crash.

Explanaition:

He took 27 minutes to get the switch.

Mean while train A do 72 km, and train B 54 km. 72+54=126 less then 140.

• Yes , he will be on time because :

He need 0,45 h for goes to switch 6,5km/14km/h =0,45h;

Trains for this time go 126 km - this is 0,45h*(120+160)km/h=126km

Beacouse 126km < 140km - that is ok .

• Controller will arrive after 27 minutes at the security switch.

Based on their speed, the trains will collide in 30 minutes.

As a conclusion, we are gratefull the controller is quick enough to save both trains.

• The two trains will collapse in 30 minutes. Train A will do 80km et train will do 60 km in 30 minutes so 140km covered. In 30 minutes, the supervisor runs 7km and he has 6.3km to run. So he'll get there just in time.

• He will arrive on time.

He needs 27 min to arrive (0.45h) to manual switch. In that time, Train A will do 72km and train B 54km. That made a total distance of 126km. Less tan the 140km between them.

• çarpışmazlar . iki tren 30 dakika sonra çarpışcak,ama görevli 27 dakika sonra orada olur ve çarpışmayı önler.

they do not collide.two trains collide after 30 minutes,but the attendant will be therem after 27 minutes and prevents the collision..

• :большой палец вверх:

• Yes he will be able to save the trains ,

explanation: the trains will meet in 30 minutes , train A needs 30 min for 80KM and train B needs 30 min fpr 60KM , together 140KM

the superviser needs 27 minutes for the 6300 meters , so he will be in time