
How does doubling the diameter of a circle change its area?
Answer
468.3k+ views
Hint: Here, we will find the area of the circle with the given diameter and the area of the circle whose diameter is doubled by using the area of the circle formula. We will use both the area of the circles, to find the change in the area of the circle. Thus, the change in the area of a circle whose diameter is doubled is the required answer.
Formula Used:
We will use the following formula:
1. Radius is half the Diameter i.e.,
2. Area of the circle is given by where is the radius of the circle.
Complete step by step solution:
Let us consider a circle whose original diameter is .
We know that Radius is half the Diameter i.e.,
We know that the Area of the circle is given by where is the radius of the circle.
Now, by using the radius of the circle in the area of the circle formula, we get
Applying the exponent on the terms, we get
………………………………………………………
Now, let us consider the circle whose diameter is double the diameter of a circle.
So, we get
We know that the Area of the circle is given by where is the radius of the circle.
Now, by substituting in the area of the circle formula, we get
Substituting in above equation, we get
Applying the exponent on the terms, we get
………………………………………………………
Now, by substituting equation in , we get
Multiplying 4 on both the sides, we get
Therefore, if the diameter of the circle is doubled, then the area of the circle is four times larger than the area of the circle with diameter .
Note:
We know that Circle is a two dimensional curve whose distance from the center to any point on the curve is a constant which is called the radius of the circle. Area of a circle is the region occupied by a circle. We should remember that when finding the area of the circle, we will use the radius of the circle and not the diameter of the circle. We should remember that if the diameter is doubled, then the radius is the original diameter.
Formula Used:
We will use the following formula:
1. Radius is half the Diameter i.e.,
2. Area of the circle is given by
Complete step by step solution:
Let us consider a circle whose original diameter is
We know that Radius is half the Diameter i.e.,
We know that the Area of the circle is given by
Now, by using the radius of the circle in the area of the circle formula, we get
Applying the exponent on the terms, we get

Now, let us consider the circle whose diameter is double the diameter of a circle.
So, we get
We know that the Area of the circle is given by
Now, by substituting
Substituting
Applying the exponent on the terms, we get
Now, by substituting equation
Multiplying 4 on both the sides, we get
Therefore, if the diameter of the circle is doubled, then the area of the circle is four times larger than the area of the circle with diameter
Note:
We know that Circle is a two dimensional curve whose distance from the center to any point on the curve is a constant which is called the radius of the circle. Area of a circle is the region occupied by a circle. We should remember that when finding the area of the circle, we will use the radius of the circle and not the diameter of the circle. We should remember that if the diameter is doubled, then the radius is the original diameter.
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