The laws of physics can be directly referenced when examining how a playground slide works. Several forces have an effect on the efficiency of a slide, with the most obvious being the force of gravity. Gravity is a constant force that exerts itself on anything that has mass. However, gravity is not the only force that determines the speed or acceleration of an object, or person, traveling down a slide.
The Earth's gravitational pull exerts a downward force on everything on the planet. When someone sits at the top of a slide, gravity is the constant force that pulls the person directly downward. Without the force of gravity pulling a person, a slide wouldn't work at all. Gravity is a core physics concept that affects nearly everything, including playground equipment.
While gravity is an essential element of physics to a playground slide, friction is of equal importance. Friction works against gravity to slow a person's descent on a slide. Friction is a force that occurs whenever two objects rub against each other, such as a slide and a person's backside. Without friction, a slide would accelerate the rider too quickly, resulting in possible injury. Certain materials called lubricants can reduce the effects of friction. This is why water park slides are much faster than playground slides; the water acts as a lubricant. Sitting on wax paper can also reduce the amount of friction.
Newton's first law of motion establishes a physics concept referred to as inertia. According to The Physics Classroom, Newton's law can be summarized as "An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force." The object (the person) is at rest at the top of the slide. The object, or person, stays at rest until he is pushed, either by himself or someone else. After the push, he accelerates until he reaches a maximum velocity and stays in motion until he is stopped by another force. This is inertia.
Kinetic and Potential Energy
When a person first sits at the top of a slide, she contains potential energy. Potential energy is any stored energy, and exists in any object or being capable of falling or moving. As she begins to slide, the potential energy is converted to kinetic energy. Any object that is in motion contains kinetic energy. The amount of kinetic energy depends on mass and speed. So, the kinetic energy of a person sliding down a slide depends on how much the person weighs and how fast the person is going, which are interrelated factors. No matter which way a person is traveling down a slide, and no matter which angle, that person contains kinetic energy.
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