The Roller Coaster Rails and The Roller Coaster Cart

The roller coaster rails and the roller coaster cart is a compound machine. The pulley and the wheel and axle is in the roller coaster rails and cart. The pulley is in the roller coaster rails and the wheel and axle is in the cart of the roller coaster. The pulley is used in the roller coaster rails because when the rails go up there must be a chain to make the carts go up and so the pulley is in the roller coaster rails. The wheel and axle is in the cart of the roller coaster because to make the cart move on the rails smoothly and sometimes the wheel of the cart is usually stuck down with the rails so the cart won't come off.