🛒 Newton's Second Law (F = ma)

📖 The Physics

Newton's second law is the heart of mechanics: a net force makes a mass accelerate. But "net" is the key word. The push (blue) first has to overcome friction (red); only the leftover — the net force — actually accelerates the cart.

And the heavier the cart, the less it accelerates for the same net force, because mass is a measure of how much a body resists changes in motion.

Turn the force below the friction value and the cart never moves. Add mass and the same force gives a smaller acceleration.