wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Two concentric circles are of radii 5 cm and 3 cm. Find the length of the chord of the larger circle (in cm) which touches the smaller circle.

Open in App
Solution






Let the radius of the bigger circle be 'R' and the radius of the smaller circle be 'r'.
It is given that R=5cm=OA and r=3cm=OP and AB is the chord whose length we have to find.
AP=BP and OP⊥AB(radius is perpendicular to a chord and it divides the chord into two equal parts)
therefore, ΔOPA is a right angled triangle
where, O²+Ap²=OA²
(3)²+AP²=(5)²
9+AP²=25
AP²=25-9
AP²=16
AP=4cm
Since AP=BP=4cm
therefore, AB=AP+BP
AB=4+4
AB=8cm


flag
Suggest Corrections
thumbs-up
3
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Circles and Their Chords - Theorem 3
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon