Question

We do not see a car moving as a wave on the road. Why?

Answer 1

That is because the size of the car is very big. The debroglie wavelength of a particle is given by λ = h/p = h/mv, where h is the Planck's constant = 6.63 x 10-34 J.s, m the mass of the particle and v its speed. Here the numerator is very small and the denominator is large and hence the wavelength is too small to observe.