Question

Пуля,летящая со скоростью 400 м/с ,ударяется о земляной вал и проникает в него на глубину 20 см. Cколько времени двигалась пуля внутри вала? ?

Answer 1

Uср=(Uo+U)/2 
t=d/Ucp=d/((Uo+U)/2)=2d/U+Uo=2*0,2/400=0,001 c=1 мс 

Answer 2

Calculation of Time the Bullet Moved Inside the Earth Embankment

To calculate the time the bullet moved inside the earth embankment, we need to determine the distance traveled by the bullet inside the embankment and divide it by the bullet's velocity.

Given: - Bullet velocity: 400 m/s - Penetration depth: 20 cm (or 0.2 m)

To find the time the bullet moved inside the embankment, we can use the formula:

Time = Distance / Velocity

The distance traveled by the bullet inside the embankment is equal to the penetration depth, which is 0.2 m.

Plugging in the values, we have:

Time = 0.2 m / 400 m/s

Calculating this, we find:

Time = 0.0005 seconds

Therefore, the bullet moved inside the earth embankment for approximately 0.0005 seconds.

Please note that the above calculation assumes a constant velocity for the bullet throughout its travel inside the embankment.