Why is it dangerous to stand on the edge of the platform near the railway line when the train is passing by?

A train,standing at the outersignal of a railway station blows a whistle of frequency 400 Hz in still air. What is the frequency of the whistle for a platform observer when the train approaches the platform with a speed of 10 m s^-1

A train, standing in a station-yard, blows a whistle of frequency 400 Hz in still air. The wind starts blowing in the direction from the yard to the station with a speed of 10 m s^-1 . What are the frequency, wavelength, and speed of sound for an observer standing on the station’s platform? Is the situation exactly identical to the case when the air is still and the observer runstowards the yard at a speed of 10 m s^-1 ? The speed of sound in still air can be taken as 340 m s ^-1 .

A train,standing at the outersignal of a railway station blows a whistle of frequency 400 Hz in still air. What is the frequency of the whistle for a platform observer when the train. recedes from the platform with a speed of 10 m s^-1 ?

A train travelling on one of two intersecting railway lines, subtends at a certain station on the other line, an/ angle alpha when the front of the carriage reaches the junction and an angle beta when the end of the carriage reaches it. Then, the two lines are inclined to each other at an angle theta , show that 2 cot theta=cot alpha-cot beta

The speed of rotation of a person with some weights in his hands and standing on a rotating platform increases as he draws his arms close to his chest.Why?Explain.

Why is the pressure on ground more when a man is walking than when he is standing ?

The radius of curvature of a railway line at a place is 40000m.the train is running at 20 m s^-1 .the distance between the two rails is 1.5 m.Find the elevation of the outer rail over the inner one so that the train may be able to run safely.