when does an object react with its terminal velocity? give an example from daily life.?

Question

i need this by tonight, its my science hw!! if i dont give this question ibn tomorrow i get 33.3 points of... some one help me plzz...

i mean like when does an object react with its terminal velocity? like when does it happen an give an example form daily life.

Answer 1

For example, the terminal velocity of a skydiver in a free-fall position with a semi-closed parachute is about 195 km/h (120 mph or 54 m/s). This velocity is the asymptotic limiting value of the acceleration process, since the effective forces on the body more and more closely balance each other as it is approached. In this example, a speed of 50% of terminal velocity is reached after only about 3 seconds, while it takes 8 seconds to reach 90%, 15 seconds to reach 99% and so on.

Higher speeds can be attained if the skydiver pulls in his limbs (see also freeflying). In this case, the terminal velocity increases to about 320 km/h (200 mph or 89 m/s), which is also the maximum speed of the peregrine falcon diving down on its prey. Competition speed skydivers fly in the head down position reaching even higher speeds. The current world record is 614 km/h or 382 mph.

An object falling will fall 9.81 meters per second faster every second (9.81 m/s²). The reason an object reaches a terminal velocity is that the drag force resisting motion is directly proportional to the square of its speed. At low speeds the drag is much less than the gravitational force and so the object accelerates. As it speeds up the drag increases, until eventually it equals the weight. Drag also depends on the cross sectional area. This is why things with a large surface area such as parachutes have a lower terminal velocity than small objects like cannon balls.

Mathematically, terminal velocity is given by

.

Note that the density increases with decreasing altitude, ca. 1% per 80 m (see barometric formula). Therefore, for every 160 m of falling, the "terminal" velocity decreases 1%. After reaching the local terminal velocity, while continuing the fall, speed decreases to change with the local terminal velocity.

2mg
VT= ________
P AC d

where

Vt is the terminal velocity,
m is the mass of the falling object,
g is gravitational acceleration at the Earth's surface,
Cd is the drag coefficient,
ρ is the density of the fluid the object is falling through, and
A is the object's cross-sectional area.
So it can be said that, on Earth, the terminal velocity of an object changes due to the properties of the fluid, mass and the cross sectional area of the object.

This equation is derived from the drag equation by setting drag equal to mg, the gravitational force on the object.




** Hope that helps
Your instructor will wt to know where you obtained your information, and that you understand the math and terminology.
I suggest you go to this site and attempt to understand what it is saying.

Msg me and let me know how you did.

Bye

Answer 2

Your question actually doesn't make much sense... What do you mean by "react with its terminal velocity?"

When an object reaches its terminal velocity, the speed will no longer increase. That means, it will remain in constant speed. An only ordinary object that reaches this velocity that I am aware of, is a rain drop. The actual speed depends on size of the drop itelf, which is determined by the temperature and surrounding air's moisture. It is somewhere between 2 to 9 meters per second.

Answer 3

in case you have been status in front of a twister and the wind finally picked you up, you will possibly fly away. The wind on your face, mandatory to maintain you aloft, may be corresponding to the terminal velocity of falling off an extremely severe cliff. that's maximum in lots of situations used to describe a falling merchandise that doesn't velocity up any further because of the fact friction of the air rushing by using him equals the stress of his mass being attracted down by using gravity.

Answer 4

im not sure i know what you mean, if you mean when does an object reach its terminal velocity it is when the fluid resistance (resistance of air on a macroscopic object is linear) completely balances the force due to gravity,,, that is acceleration is zero