According to Newton's second law, $F = ma$. If acceleration is zero then the force must be zero, but assuming you have an object moving with a constant velocity of say $2 \mathrm{ms^{-1}}$, and that object strikes you, then obviously some sort of 'force' would be felt by you, so my question is what do you call that 'force' since it actually is not a 'force' and is there an equation to calculate it?
Answer
Some students learning physics for the first time mistakenly think that objects that are accelerating have force.
Force is not a property possessed by an object, but rather something you do to an object that results in the object accelerating (changing its speed), given by the equation F = ma.
That is, Forces cause acceleration, not the other way around. This means that if you observe an object accelerating, then it implies a force is acting on the object to cause such an acceleration.
In this case, as the object strikes the hand, your hand applies a force to the ball causing it to slow down (decelerate), and the ball applies an equal and opposite force to your hand causing it to accelerate ever so slightly (Newton's third law), which is detected by your sensory neurons.
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