A bullet of mass 0•5kg has a speed of 40m/s. What is its kinetic energy? If it hits a wall of which the average resistive force is 10,000N , calculate the distance penetrated by the bullet.

(1/2) m v^2 = (1/2)(1/2) (1600) = 400 Joules

(pretty heavy bullet by the way)
work done = force * distance
400 = 10,000 * distance

Did you know?

Did you know that an object's kinetic energy is determined by its mass and velocity? In this example, a bullet with a mass of 0.5kg and a speed of 40m/s has a certain amount of kinetic energy. Kinetic energy can be calculated by using the formula KE = (1/2)mv², where KE represents the kinetic energy, m is the mass, and v is the velocity. Now, let's consider what happens when this bullet hits a wall. The wall exerts a resistive force on the bullet, which can be measured in Newtons (N). In this case, the average resistive force is 10,000N. By using the formula work = force x distance, we can find the distance penetrated by the bullet. Since the work done on the bullet by the resistive force of the wall is equal to the change in kinetic energy, we can rearrange the formula to find the distance penetrated, which is given as: distance penetrated = (change in kinetic energy) / (resistive force).