Here, we have to find out the force which gives rise to simple harmonic motion. We know that, Simple harmonic motion is a motion that is neither driven nor damped (i.e. no friction to slow the motion); the motion is periodic as it repeats itself at standard intervals in a specific manner. The force law which gives rise to simple harmonic motion is F = -kx, where the force is directly proportional to the displacement. (the equation is derived from Hooke’s Law) Displacement x must be of first degree. There must be a –ve sign, which shows that the force is opposite to the displacement. That is, F = -kx gives rise to simple harmonic motion.