Acart of mass 20 kg, initially at rest, is pushed with a net force of 40 n on a flat surface. if the cart is pushed 5 m, what is the final kinetic energy (ke)? what is the final velocity? (assume no heat losses.)

Using the theorem of kinetic energy
1/2mVf² - 1/2mVi²= WF + Wp,     Wp=0
WF = F. AB, AB=5m and F= 40N, m=20kg
so the final kinetic  is KEf= 1/2mVf² = WF =F. AB= 40*5=200J

the final velocity is 1/2mVf² =200, implies   Vf= sqrt(20)=2sqrt(5)m/s

Less force and energy was applied