Circle Area Formula Quiz - Quiz Questions
Test your understanding of the 'Rearrangement' limit concept and the derivation of the circle area formula.
1. In the circle rearrangement experiment, as the number of sectors $n$ increases, what shape does the rearranged figure increasingly resemble?
- A. Triangle
- B. Trapezoid
- C. Rectangle
- D. Square
2. What geometric quantity of the circle corresponds to the 'height' of the approximate rectangle?
- A. Diameter (d)
- B. Radius (r)
- C. Circumference (C)
- D. Chord Length
3. What is the 'width' of the rearranged rectangle equal to?
- A. Circumference (C)
- B. Half the Circumference ($\pi r$)
- C. Diameter (d)
- D. Radius (r)
4. Based on the derived formula $Area = \text{Width} \times \text{Height}$, what is the formula for the area of a circle?
- A. $2\pi r$
- B. $\pi r^2$
- C. $2\pi r^2$
- D. $\pi^2 r$
5. If the radius of a circle is $r=10$ and we take $\pi=3.14$, what is its area?
- A. 31.4
- B. 62.8
- C. 314
- D. 100
6. If we don't change the radius but cut the circle into more sectors (e.g., increasing from 16 to 64), what happens to the area of the rearranged figure?
- A. Increases
- B. Decreases
- C. Remains unchanged
- D. Cannot be determined
7. If the radius of the circle is doubled, how many times larger does the area become?
- A. 2 times
- B. 4 times
- C. 8 times
- D. Unchanged
8. Why do we use the concept of 'limit' ($n \to \infty$)?
- A. Because computers can't handle large numbers
- B. To make the shape look better
- C. Because only with infinite cutting does the rearranged shape strictly equal a rectangle, eliminating error
- D. Because ancients liked complex math