What is terminal velocity?
Any falling object starts at 0 downward velocity (unless it has been pushed down, which only gets you to terminal V faster). The force gravity exerts on the object increases the object’s velocity. The object’s velocity will continue to increase because of gravity until the object runs into something, namely the ground. Or at least this is how physics goes in a vacuum where there is no air resistance. Air resistance , or drag, happens because there are particles in the air (oxygen, hydrogen, etc), and as an object falls the object interacts with the particles (by dropping on them). For every action there is an equal and opposite reaction, and so these particles also exert a force on the falling object (by pushing back up). Granted this is not enough force to push the object back up, or even to stop the object. As the velocity of the object increases, so does the amount of force the air resistance pushes up on the object. Eventually the force gravity exerts down on the object and the for
Terminal velocity is the term for the state an object reaches when the force of drag acting on it is equal to the force of gravity acting on it. When an object reaches its terminal velocity, it no longer accelerates, remaining at whatever velocity it was already traveling or else slowing down. As an object accelerates, the amount of drag exerted on it increases. This means that more force is necessary to sustain the same level of acceleration. If that external force is increasing, as in a car or plane, then the object can be accelerated well past its terminal velocity. If, however, the only force being exerted on it is the force of gravity, then eventually the drag will become as great as the static force of gravity, and the object will cease to accelerate. An object may also decelerate towards terminal velocity, if it was initially moving faster than terminal velocity. This may be because it entered from somewhere with less drag, such as the thinner upper atmosphere, or because it was
Video Transcript What Is Terminal Velocity? When we talk about terminal velocity, we’re talking about a free falling object. The free falling object is pulled by gravity towards the center of the Earth. Now this object is opposed by friction in air. And that force is called air drag. Let me illustrate. Here’s this object. And it’s falling with a force Fg. Force by gravity. Now the drag force is exactly opposite. Fd. Now when Fg equals Fd. Then you’re in equilibrium. And you have reached a velocity that is constant. And it is called the Terminal Velocity.
