A force F acts in the forward direction on a cart of mass m. A friction force f opposes this motion.
(a) Use Newton’s second law and show that the acceleration of the cart is F - f/m.
(b) Show that if the cart’s mass is 4.0 kg, the applied force is 12.0 N, and the friction force is 6.0 N, the cart’s acceleration is 1.5 m/s².