A projectile weighing 5 kg acquires a speed of 300 m / s when fired. Find the average force if the barrel length is 0.9m.

Data: m (projectile mass) = 5 kg; V (the speed that the projectile acquired when fired) = 300 m / s; L (barrel length, path traveled by the projectile) = 0.9 m; V0 (initial velocity of the projectile) = 0 m / s.

The average force that acted on the projectile when fired can be expressed from the equality: ΔEk = A.

Ek1 – Ek2 = F * S.

m * V ^ 2/2 – m * V02 / 2 = F * L.

m * V ^ 2/2 = F * L, whence F = m * V ^ 2/2 L.

Calculation: F = 5 * 300 ^ 2 / (2 * 0.9) = 250 * 10 ^ 3 (250 kN).

Answer: When fired, an average force of 250 kN acted on the projectile.