Two points that lie on the circles of different bases of the cylinder are connected by a segment.
Two points that lie on the circles of different bases of the cylinder are connected by a segment. Find its length if the radius is 10 cm, the height is 17 cm, and the distance from the axis to the segment is 4 cm.
Let point A lie on the upper circle of the base, point B lies on the lower circle of the base, O is the center of the lower circle.
Let’s find the length AB.
Points A and B are located so that if they were located on the same circle, they would be on opposite sides of the radius.
Point A will be projected onto the lower base.
We get a segment AA1 equal to the height of the cylinder, triangle A1AB is rectangular.
The chord A1B is located from the axis at a distance OH = 4 cm, where OH is the height of an isosceles triangle A1OB with sides AO = OB = r = 10 cm.
Then A1B = 2 * HB.
From right triangle НОВ:
HB ^ 2 = OB ^ 2 – OH ^ 2 = 100 – 16 = 84 cm ^ 2.
A1B ^ 2 = 4 * HB ^ 2 = 4 * 84 = 336 cm ^ 2.
From the triangle A1AB by the Pythagorean theorem we find AB.
AB ^ 2 = (AA1) ^ 2 + (A1B) ^ 2 = 17 ^ 2 + 336 = 289 + 336 = 625 cm ^ 2.
AB = 25 cm.