Question

If a table tennis ball hits a person then the person will not get hurt but if a cricket ball hits a person then he will get hurt explain using newtons 2nd law

Answer 1

Newton's Second LawNewton's Second LawThe Big MisconceptionFinding AccelerationFinding Individual ForcesFree Fall and Air ResistanceDouble TroubleNewton's first law of motion predicts the behavior of objects for which all existing forces are balanced. The first law - sometimes referred to as the law of inertia - states that if the forces acting upon an object are balanced, then the acceleration of that object will be 0 m/s/s. Objects at equilibrium (the condition in which all forces balance) will not accelerate. According to Newton, an object will only accelerate if there is a net or unbalanced force acting upon it. The presence of an unbalanced force will accelerate an object - changing its speed, its direction, or both its speed and direction.
 Newton's second law of motion pertains to the behavior of objects for which all existing forces are notbalanced. The second law states that the acceleration of an object is dependent upon two variables - thenet force acting upon the object and the mass of the object. The acceleration of an object depends directly upon the net force acting upon the object, and inversely upon the mass of the object. As the force acting upon an object is increased, the acceleration of the object is increased. As the mass of an object is increased, the acceleration of the object is decreased.  The BIG EquationNewton's second law of motion can be formally stated as follows:The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.This verbal statement can be expressed in equation form as follows:a = Fnet / mThe above equation is often rearranged to a more familiar form as shown below. The net force is equated to the product of the mass times the acceleration.Fnet = m • aIn this entire discussion, the emphasis has been on the net force. The acceleration is directly proportional to the net force; the net force equals mass times acceleration; the acceleration in the same direction as the net force; an acceleration is produced by a net force. The NET FORCE. It is important to remember this distinction. Do not use the value of merely "any 'ole force" in the above equation. It is the net force that is related to acceleration. As discussed in an earlier lesson, the net force is the vector sum of all the forces. If all the individual forces acting upon an object are known, then the net force can be determined. If necessary, review this principle by returning to the practice questions in Lesson 2. Consistent with the above equation, a unit of force is equal to a unit of mass times a unit of acceleration. By substituting standard metric units for force, mass, and acceleration into the above equation, the following unit equivalency can be written.1 Newton = 1 kg • m/s2The definition of the standard metric unit of force is stated by the above equation. One Newton is defined as the amount of force required to give a 1-kg mass an acceleration of 1 m/s/s.