Radius of circle in which a chord of length $\sqrt {2}$ makes an angle $\cfrac { \pi }{ 2 } $ at the centre, is
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Radius of circle in which a chord of length $\sqrt {2}$ makes an angle $\cfrac { \pi }{ 2 } $ at the centre, is
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For a chord of length L subtending angle theta at center, L = 2*r*sin(theta/2). sqrt(2) = 2*r*sin(pi/4) = 2*r*(1/sqrt(2)) = r*sqrt(2). So r = 1.
The two radii connecting to the ends of the chord form a right angle of pi/2 radians, creating an isosceles right triangle with the chord. In this triangle, the two equal sides are the radii of the circle, and the hypotenuse is the chord of length square root 2. Using the Pythagorean theorem, r squared plus r squared equals the square root of 2 squared, resulting in the equation 2r^2 = 2. Solving this gives a radius of 1.