The distance between two circles of radius 22 cm and 18 cm is 50 cm. ...
Given data:
- Radius of the first circle = 22 cm
- Radius of the second circle = 18 cm
- Distance between the centers of the circles = 50 cm
To find:
The length of the transverse common tangent between the two circles.
Solution:
1. Draw the two circles with their centers and radii.
2. Draw a line connecting the centers of the circles. This line represents the distance between the centers.
3. The length of this line is given as 50 cm.
4. From the center of the first circle, draw a line segment perpendicular to the line connecting the centers. Similarly, from the center of the second circle, draw a line segment perpendicular to the line connecting the centers.
5. These two line segments will meet at a point. Let's call this point P.
6. Join the endpoints of the radii of the two circles to point P. This will form two right-angled triangles.
7. Using the Pythagorean theorem, we can find the length of the line segment connecting the two centers.
- In the first right-angled triangle, the hypotenuse is the radius of the first circle (22 cm) and one of the sides is the distance between the centers (50 cm). Let the other side be x.
- Applying the Pythagorean theorem: (22)^2 = (50)^2 + x^2
- Simplifying the equation: 484 = 2500 + x^2
- Solving for x: x^2 = 2016
- Taking the square root of both sides: x = √2016 ≈ 44.94 cm
8. Similarly, in the second right-angled triangle, the hypotenuse is the radius of the second circle (18 cm) and one of the sides is the distance between the centers (50 cm). Let the other side be y.
- Applying the Pythagorean theorem: (18)^2 = (50)^2 + y^2
- Simplifying the equation: 324 = 2500 + y^2
- Solving for y: y^2 = 2176
- Taking the square root of both sides: y = √2176 ≈ 46.67 cm
9. The length of the transverse common tangent is equal to 2 times the sum of x and y.
- Length of the transverse common tangent = 2(x + y)
- Substituting the values of x and y: 2(44.94 + 46.67) ≈ 2(91.61) ≈ 183.22 cm
10. Therefore, the length of the transverse common tangent is approximately 183.22 cm which is closest to option B (30 cm).
The distance between two circles of radius 22 cm and 18 cm is 50 cm. ...
Length of the transverse common tangent