Αποτελέσματα Αναζήτησης
21 Νοε 2022 · Air resistance—drag, as it's usually known—follows on from the distinction between laminar and turbulent flow. When a sports car speeds through the air, the flow remains relatively laminar; when a truck plows through it, there's much more turbulence.
4 Μαρ 2017 · However, one must remember that in a very thin layer (called the boundary layer—shown by δ) near the vehicle surface there is a so-called “skin friction” which also adds to the drag coefficient (but its contribution in automobiles to C D is usually very small).
The magnitude of the frictional force has two forms: one for static situations (static friction), the other for situations involving motion (kinetic friction). What follows is an approximate empirical (experimentally determined) model only.
A speeding stock car pierces the air as it travels. Air swooshes over the top of the car and is deflected by the spoiler attached to the rear deck. If another car trails immediately behind, nose to tail, it continuously enters airspace affected by the car in front.
It's a force the engine is exerting against itself (to some fraction of that number) due to idling. It is also the constant electronic loads on the battery... and the charging of the battery itself. It's not the friction of the wheels on the road of air on the car.
Air resistance is sometimes referred to as “air friction,” but although it has dissipative qualities similar to those of friction (as we will see when we study energy), the mechanism by which it functions is quite different.
The force that keeps the block from moving acts to the left and is called the frictional force, Ff. As long as the block is in equilibrium, F = Ff. Since the block is stationary, we call this frictional force the force of static friction. The word static means stationary, or unchanging.
