A person pushes a 27.4 kg car at a constant velocity of 17.1 m/s across a horizontal floor for 78.3 s. Find the energy dissipated by the
frictional force ?
(given that the coefficient of kinetic friction Hk = 0.4)
V
friction opposing the motion
Fk
Energy =

The de broglie relation λ=h/p can be rewritten in terms of the wave number k as p=kℏ. recall that wave number is defined by k=2π/λ. using the fact that λ=v/f, find the wave numbers k1 and k2 corresponding to frequencies f1 and f2. express your answer as two expressions

What is the conversion factor between kg/m^3 and g/m^3. express your experimental values for the densities in kg/m^3.

An initially unpolarized light if intensity 500 w/m^2 passes through four polarizers. the transmission axis between adjacent polarizers is 45∘. what percentage of the initial intensity is transmitted by the system?