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How do you calculate drag coefficient when you are not given drag force?
Wiki User
∙ 11y ago
Using empirical correlations such as the Dallavalle equation or a chart which plots Drag coefficient vs. Reynolds Number.
Wiki User
∙ 11y ago
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What is the unit used to measure drag force?
(Low altitudes, normal temperatures / pressures, ordinary speeds.) > Drag due to moving through the air, depends on the velocity and the objects drag coefficient in the equation: > drag force (newtons) = velocity2 * drag coefficient > some (typical) drag coefficients: saloon car : 0.40 115 hp motorcycle ( with fairing) 0.23 person in freefall : 0.16
Why does a parachutist have two terminal velocities?
Because the drag coefficient increases when the chute opens..Force down (newtons) = mass (m) * acceleration due to gravity (g)Force up (newtons) = velocity2 * drag coefficient.Terminal velocity is where up and down forces balance.Say mass (m) = 100 kg, g = 9.82, then force down = m * g = 982 newtons, say terminal velocity (v) prior to chute opening = 70 m / s, then force down = force up so 982 = v2 * drag coefficient, so drag coefficient = 982 / 4900 = 0.2without chute.Terminal velocity with chute open, say 8 metres / sec, so drag coefficient= 982 / 64 = 15.34 with chute open.
What force changes when a sky diver's parachute opens what force stays the same?
The force down remains constant.force down (newtons) = (mass (kg) * acceleration due to gravity ((m/s)/s) ).The force up varies with velocity and drag coefficient ( which increases significantly when the chute opens).force up (newtons) = velocity2 * drag coefficient
What force would change if a parachutist opens the parachute during the fall What will happen to the net force and acceleration over time after that?
At terminal velocity (forces balanced): drag coefficient changes when chute is opened, increasing drag force , net force is upward, deceleration takes place to new (lower) terminal velocity.
The SI unit of the drag force?
If you consider drag as a force, that would be Newtons.If you consider drag as a force, that would be Newtons.If you consider drag as a force, that would be Newtons.If you consider drag as a force, that would be Newtons.
What are formulas to calculate drag coefficient when you don't have drag force?
Using empirical correlations such as the Dallavalle equation or a chart which plots Drag coefficient vs. Reynolds Number.
What is the definition of the push of air force?
Force on moving object by air friction: velocity2 * objects drag coefficient > Force on stationary object by wind: wind speed2 * objects drag coefficient
What is frictional resistance due to motion through air?
This frictional resistance known as "air resistance" is the drag force. The drag force changes with the drag coefficient of the object in motion.
What is the definition of drag coefficient?
Simply put, the coefficient of drag (Cd) is a way to quantify the various factors that affect, and result in, drag on an aerodynamic object. See the link below for an excellent discussion of drag coefficient on the NASA website. An airplane has 4 forces acting upon it and one of them is Drag, a force in the opposite direction of flight. Aeronautical engineers study the forces on a wing but found it easier to use non-dimensional measuresments. Drag is measure in Force (lbs). But Drag Coefficient is a value of force/force. This allows the engineer to produce charts for the numerous airfoil wing designs and have a Drag Coeffecient Chart that can be used for various sizes of wing applications.
What is drag force and what are its factors on which it depends?
Drag force is the resistance to motion of the object offered by the medium through which it travels, its value depends on the viscosity of the medium, and the shape, size and surface texture of the object. Note: for any given object, the drag force is equal to the square of the velocity * the drag coefficient of the object (rolling resistance is extra in the case of cars etc.)
I want to calculate how many Newtons it takes to drag a sticky tennis shoe sole over linoleum. What formula do I use?
You use the formula of finding force of friction. The eq'n is: Force of friction = the coefficient of friction multiplied by normal force.
What force exert by parachutes?
Drop any object from a plane and the downward force due to the mass will eventually be matched by an upward force due to air resistance (terminal velocity). This terminal velocity depends on the objects drag coefficient, what the parachute does is present a drag coefficient sufficient to give the required terminal velocity for landing . > You need no more than say 6 metres / second landing velocity, effectively this is the terminal velocity with the chute open. Using body mass of 80 kg and acceleration due to gravity of 10 (m/s)/s, this gives a downward force of ( 80 * 10 ) 800 newtons. To balance this at landing velocity, you need a drag coefficient calculated from: 800 = velocity2 * drag coefficient , so: drag coefficient = 800 / velocity2 = 22.22 > Compare this to the pre chute deployment velocity of around 80 metres / second, giving a drag coefficient of: drag coefficient = 800 / 6400 = 0.125
Why does the book fall on the floor before the paper does if dropped at the same time from the same height?
air resistance is everything, if both were dropped at the same time from the same height in a vacuum, they would accelerate equally, hitting the floor at the same time..acceleration (a) is given by:a = force / mass.force (down) is given by mass (kg) * acceleration due to gravityregardless of the mass, the acceleration in a vacuum would be the same..Once air is introduced however, any motion would be resisted by the air, according to the equation: force (up) = (velocity squared * drag coefficient).so, net force available for acceleration once in motion, at a given velocity = force (down) - force (up).if you assume same drag coefficient for both, at any given velocity, lighter object will have less acceleration, leading to heavier object hitting the floor first.notes:terminal velocity is where force down = force up.for same drag coefficient, more massive object will have greater terminal velocity..guess at drag coefficient for book / paper = 0.005
What does the force drag mean?
"Drag" is the name given to the force of air resistance, or friction in general.
Does the size and shape of an animal affects the rate of motion Does the size and shape of an animal affects the rate of motion?
for a given force, a better drag coefficient will yield a greater velocity
What is the equation for force of friction?
The equation for hydrodynamic drag force: drag force equals to fluid density times square speed of object times cross sectional area times drag coefficient and divided by two. The drag coefficient is usually dimensionless and the speed of object here refers to the speed of object in relation to the fluid.
Example of Air resistance?
Calculate drag coefficient of freefaller (prior to chute opening)>(constant) force down (in newtons) due to gravity = mass * acceleration due to gravity, say 80 * 10 = 800 newtons.>The up force (newtons) = velocity2 * drag coefficient>At terminal velocity (where up and down forces balance) the up force = 800 newtons, say terminal velocity = 70 metres / second>800 = 4900 * drag coefficient>Drag coefficient = 800 / 4900>Drag coefficient = 0.163
