The second law of motion states that1 pointto every action there is an equal and opposite reactiona body will continue to be at rest or in motion unless and external force is applied to itif the external force acting on a system of bodies is zero, then the momentum of the system remains constantthe force applied to an object is directly proportional to the mass of the object and the acceleration.

The second law of motion, also known as Newton's second law, states that the force applied to an object is directly proportional to the mass of the object and the acceleration. This can be expressed with the formula F = ma, where F is the force, m is the mass, and a is the acceleration.

Here's a step-by-step breakdown:

1. Identify the object and the forces acting on it. The forces could be gravity, friction, tension, etc.

2. Determine the mass of the object. This is usually given in problems or can be measured.

3. Determine the acceleration of the object. This can be calculated if the initial and final velocities of the object are known, using the formula a = (v_f - v_i)/t, where v_f is the final velocity, v_i is the initial velocity, and t is the time.

4. Substitute the mass and acceleration into the formula F = ma to find the force.

Remember, the direction of the force is the same as the direction of the acceleration.