Final answer:
A cart rolling on a frictionless, horizontal surface maintains a constant velocity due to the absence of friction, in accordance with Newton's first law of motion.
Step-by-step explanation:
When a cart is rolling along a frictionless, horizontal surface, it maintains a constant velocity because there is no friction to slow it down or speed it up. This situation is a practical illustration of Newtons's first law of motion, which states that an object in motion will stay in motion with the same speed and in the same direction unless acted upon by an unbalanced external force. This concept does not only apply to carts on frictionless surfaces but also to other scenarios such as a car rounding a bend at a constant speed, a merry-go-round reaching a constant rotational speed, a pendulum swinging back and forth, and a bowling ball rolling down a bowling alley.
In the absence of friction and other external forces, the motion of the cart would not be altered, leading to the answer choice (c) It maintains a constant velocity. This is different from situations where friction is present, such as when an object slides across a surface and gradually slows down due to the kinetic friction between the surfaces. Similarly, the coefficient of kinetic friction between two sliding surfaces remains constant regardless of the relative speed of the surfaces. Newton's law of universal gravitation, on the other hand, applies to orbital motions such as a planet moving around the sun and does not impact the cart on the frictionless surface.