Given a circle of radius 5 cm and centre o . OL is drawn perpendicular...
As when we draw the figure we can see that there is a right angle triangle-(LOB) Hence as OB is hypotenus,OL is perpendicular and LB is base then=>OB=5 cm ( radius )=>OL=3cm (given)Hence LB = 4 cm ( pythagorus theorum)Hence AB = (2×4) = 8cm.That's all.
Given a circle of radius 5 cm and centre o . OL is drawn perpendicular...
Problem:
Given a circle with a radius of 5 cm and center O. OL is drawn perpendicular to the chord AB. If OL = 3 cm, find the length of chord AB.
Solution:
To find the length of chord AB, we can use the properties of perpendiculars and chords in a circle. Let's break down the solution into smaller steps.
Step 1: Understand the Problem
We have a circle with a radius of 5 cm and center O. We are given that OL is perpendicular to chord AB, and OL has a length of 3 cm. We need to find the length of chord AB.
Step 2: Visualize the Problem
It is essential to have a clear visualization of the problem to solve it effectively. Draw a circle with center O and radius 5 cm. Draw a perpendicular line OL from the center O to chord AB. Label the length of OL as 3 cm.
Step 3: Identify Key Concepts
To solve the problem, we need to use the following key concepts:
1. Perpendicular from the center of a circle bisects the chord.
2. The length of the perpendicular from the center to a chord is the bisector of the chord.
Step 4: Apply Key Concepts
Since OL is perpendicular to chord AB, it bisects AB into two equal parts. Let's consider the two parts of AB as AO and BO. Since OL bisects AB, we have:
AO = BO
We know that OL = 3 cm, and the radius of the circle is 5 cm. Using the Pythagorean theorem, we can find the length of AO or BO.
Applying the Pythagorean theorem:
AO² + OL² = AL²
AO² + 3² = 5²
AO² + 9 = 25
AO² = 16
AO = 4 cm
Since AO = BO, the length of AB is the sum of AO and BO:
AB = AO + BO
AB = 4 cm + 4 cm
AB = 8 cm
Step 5: Final Answer
The length of chord AB is 8 cm.
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