How long does it take for a rocket to pass completely through a mine with a depth of 150 meters

How long does it take for a rocket to pass completely through a mine with a depth of 150 meters, if the length of the rocket is 50 meters, by how much speed is 72 km / h. Is it possible to consider a rocket as a material point.

Because the length of the rocket is necessary for calculations, it is impossible to neglect its dimensions, therefore, as a material point, the rocket cannot be considered.

Data: H (shaft depth) = 150 m; L (rocket length) = 50 m; V (constant rocket speed) = 72 km / h.

SI system: V = 20 m / s.

1) Let’s calculate the distance that the rocket needs to cover:

S = H + L = 150 + 50 = 200 m.

2) Determine the time when the rocket completely passes the mine:

t = S / V = 200/20 = 10 s.

Answer: The rocket will completely pass the mine in 10 seconds.