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23 articles trouvés pour ce sujet.
Un angle solide 1998-05-06
Giol pose la question :
Qu'est ce qu'un angle solide ?? J'ai beau chercher dans mes documents, je ne trouve rien de bien convaincant sur le sujet si ce n'est une définition qui me semble bien vague et creuse ... En vous remerciant de votre attention ( puissiez vous illustrer votre réponse par un exemple, s.v.p...)


Chris Fisher lui répond.

x+sin(x) 2020-07-24
adm pose la question :

to evaluate f(30)

use radians only or degrees

Harley Weston lui répond.
Why 1/2 in the area of a circular sector? 2018-10-26
Ariel pose la question :
In the equation for area of a sector=1/2r^2theta why is it 1/2? Please explain conceptually not algebraically.
Penny Nom lui répond.
Angle measures 2012-03-21
jogiboy pose la question :
how can i get the sine theta if the given is 3.14/3
Penny Nom lui répond.
The rate of change of the area of a parallelogram 2011-04-05
Gevork pose la question :
Let a parallelogram have sides of 8 and 12 and let vertex angle A be decreasing at a rate of 2degrees per minute. Find the rate of change of the area of the parallelogram when angle A equals 30 degrees.
Penny Nom lui répond.
Angular velocity 2010-03-17
Lindsay pose la question :
Determine the angular velocity, in radians per second, of a 14-inch car wheel, if the car is traveling at 60 miles per hour
Harley Weston lui répond.
Angular speed 2009-08-04
Mary pose la question :
The engine of a sports car rotates at 5000 revolutions per minute (rpm). Calculate the angular speed of the engine in radians per second. Use 2 radians = 1 revolution.
Penny Nom lui répond.
limit sinx/x 2009-01-30
Jackie pose la question :
how to evaluate limit sinx/x as x tends to zero if x is in degrees
Stephen La Rocque and Harley Weston lui répond.
Radians 2008-02-08
Brian pose la question :
I'm teaching Precalculus right now and will be covering the formula to convert angular speed into linear speed. My question is about the units involved. Using v=rw, if r is mearsured in feet and w is measured in radians/second then v is measured in ft/sec. What happened to the units of radians? I can't find a good way to explain why they are not part of units for velocity. Do you have a good explanation? Thanks,
Stephen La Rocque lui répond.
Radial motion 2007-11-13
abdulai pose la question :
a circular saw with diameter 18.4cm rotates at 2400rpm. What is the angular speed of a point on the edge of the saw blade in radians per second?
Penny Nom lui répond.
Is there a practical use for radian measure? 2007-10-26
Paula pose la question :
Is there a practical use for radian measure in any profession? Which professions might us radian as opposed to degree measure?
Harley Weston lui répond.
Angular speed 2007-08-05
Virginia pose la question :
the engine of a sports car rotates at 5,000 revolutions per minute (rpm). calculate the angular speed of the engine in radians per second. use 2n radians = 1 revolution
Stephen La Rocque lui répond.
What angle does the tire turn in 60s? 2007-06-04
San pose la question :
An automobile, travelling at 80km/h, is towing a trailer. The wheels of the trailer are 40cm in diameter. Through what angle does the tire turn in 60second?
Stephen La Rocque lui répond.
Angular speed 2007-01-06
Robert pose la question :
A rear wheel and tire on a John Deere 8520 farm tractor has a 39-in. radius. Find the angle (in radians) through which a wheel rotates in 12 sec if the tractor is traveling at a speed of 22 mph.
Penny Nom lui répond.
Degrees and grads 2006-04-06
Nazanin pose la question :
which angle if you add 15 to its degree we can find its measure by grad?
Stephen La Rocque lui répond.
Is 360 Really the correct value? 2005-08-15
Jack pose la question :
Considering the circumference of a "Perfect Circle" with a Diameter of 1 meter would be something like 3.14 meters, why do we use the number 360 to represent the number of degrees within that circumference?

Would it not make more sense to express the degrees in reference to the relationship to the diameter as related to pi?

That is, let's just say our "Perfect Circle" has a circumference of 3.14 meters, therefore, what we now consider as due east would change from 90 Degrees to 78.5 Degrees.

Penny Nom lui répond.
Radians 2003-01-16
Erikson pose la question :
I am a student in the 10th grade and attending advanced math at my high school. I was assign to do a report about the unit circle and the radian. But there seems to be no information available about the history of the radian; who first found out about them, which civilizations used it if any. Well, hopefully you'll assist me in this troubling question. Thank you for your kind consideration.
Penny Nom lui répond.
3 radians subtends an arc of 27 meters 2002-05-22
Kyle pose la question :
In circle O, a central angle of 3 radians intercepts an arc of 27 meters. Find the number of meters in the length of the radius.
Penny Nom lui répond.
Radian measure 2001-07-26
Amy pose la question :
i have to find out what is meant by the radian measure of an angle and compare it to the measure of an angle in degrees.
Harley Weston lui répond.
PreCalculus 2000-08-09
Angela pose la question :
Use absolute values to define the interval or pair of intervals on the real line.

<--|--- |--- ]--- |--- |--- |--- [---| ---|-->    
   18  19  20  21  22  23  24  25  26    

A car is moving at the rate of 50 miles per hour, and the diameter of its wheels is 2.5 feet.
a) Find the number of revolutions per minute that the wheels are rotating.
b) Find the angular speed of the wheels in radians per minute.

Harley Weston lui répond.
Arclength of a circle 2000-01-19
Holly pose la question :
What is the formoula for finding the arc length of a central angle of a circle??
Harley Weston lui répond.
The origin of angles 1998-02-24
Marc Poulin pose la question :
I'm currently teaching angles to students in grade 10 and I've been asked what's the origin of the terms degrees, radians and gradians.

I know that the radians come from the sexagesimal numerical system of the Babylonians but my kids wanted to know dates and persons who would have brought these terms first.
Harley Weston lui répond.

Why is a circle divided into 360 degrees? 1996-09-30
Kurtis Kredo pose la question :
I was recently wondering why a circle has been divided in to 360 degrees. When I asked my physics teacher he could not think of an answer. His guess is that it probably has to do with people long ago using the base 6 number system. I have a small inkling that it has to do with easy conversion or usage with radians or grads.
Chris Fisher lui répond.



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