Le cercle

Présentation du cercle.

Circumference of a Circle

longueur d'arc 1

Voici une animation afin de bien comprendre la notion d'angle au centre et d'arc de cercle, ainsi que leurs mesures.[br]De plus, il sera question de la proportion entre le rapport de la mesure de l'angle au centre à 360 et le rapport de la mesure de l'arc de cercle à la circonférence.

Circle Area (By Peeling!)

[b][color=#c51414]Questions for Extension and Application:[/color][/b][br][br][color=#1551b5]1) Was the "triangle" formed truly a triangle? Explain why or why not. [br][/color][br][color=#1551b5]2) What would we need to do to the number of "peels" in order to make the so-called "triangle" formed look[br] more smooth (like a true triangle) vs. a "choppy" triangle? [/color][br][br][color=#1551b5]3) Suppose an above-the-ground circular swimming pool has a radius of 12 feet. What is the area of the exposed surface of the water it contains? [br][br]4) Suppose a circular track (that surrounds grass) has a circumference of 500 feet. If 3 bags of grass seed are needed to be spread out across every 100 square feet of grass in the circular region inside this track, determine how many entire bags of grass seed will be needed to cover the entire area of the circular region surrounded by this track. [br][br]5) Suppose a 12-inch pizza (pizza with diameter = 12 inches) costs $12.00. Suppose a 24-inch pizza costs $24.00. Which pizza is the better buy? Explain why this pizza is the better buy. (Assume both pizzas have the same thickness.) [br][/color]

Aire d'un secteur du disque

Exploration de l'aire d'un secteur du disque en fonction de la mesure de l'angle au centre.

Right Circular Cylinder!

[color=#000000]Interact with the applet below for a few minutes. Then answer the questions that follow.  [br][/color]

Nautile

On obtient un nautile en traçant une succession d'arcs de cercle correspondant à des quarts de cercle. Quelle est la longueur de ce nautile constitué de quatre quarts de cercle ?

L'aire d'un anneau

Calcule l'aire de la région bleue.

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