A 7.5 kg cannon ball leaves a canon with a speed of 185 m/s. Find the average net force applied to the ball if the cannon muzzle is 3.6 m long.

F = 35651 [N]

Explanation:

To solve this problem we must use Newton's second law, which tells us that the sum of forces is equal to the product of mass by acceleration.

But first, we must use the following equation of kinematics to find acceleration.

where:

Vf = final velocity = 185 [m/s]

Vi = initial velocity = 0 (the cannon ball is at rest in the first moment)

a = acceleration [m/s²]

x = distance = 3.6 [m]

Now replacing these values into the equation:

(185)² = 0² + (2*a*3.6)

34225 = 7.2*a

a = 34225/7.2

a = 4753.5 [m/s²]

Now using Newton's second law we have:

F = m*a

where:

F = force [N]

m = mass = 7.5 [kg]

F = 7.5*4753.5

F = 35651 [N]

answer: he got 23

explanation:

12000j is work done