F ∝ dp / dt [ Greater the change in momentum, greater is force ] F = k dp / dt F = dp / dt F = d / dt( mv) Let, m: mass of the body be constant F = m dv / dt F = ma o
Newton’ s Second law is consistent with the First law F = ma If F = 0, then a = 0 According to First law, if a = 0, Then F = 0 Thus, both the laws are in sync.
o
Vector form of Newton’ s Second law
Fx = dpx / dt = max
Fy = dpy / dt = may
Fz = dpz / dt = maz o
Newton’ s Second Law was defined for point objects. For larger bodies,
o a: acceleration of the centre of mass of the system. o F: total external force on the system.