\(\frac{25}{4\sqrt3}\)
\(\frac{25\sqrt3}{2}\)
\(\frac{25}{\sqrt3}\)
\(\frac{25}{2\sqrt3}\)
The correct answer is (D) : \(\frac{25}{2\sqrt3}\)
Altitude of equilateral triangle,
\(\frac{\sqrt3l}{2}=\frac{5}{\sqrt2}\)
\(l=\frac{5\sqrt2}{\sqrt3}\)
Area of triangle
\(=\frac{\sqrt3}{4}l^2=\frac{\sqrt3}{4}.\frac{50}{3}=\frac{25}{2\sqrt3}\)
A bob of mass \(m\) is suspended at a point \(O\) by a light string of length \(l\) and left to perform vertical motion (circular) as shown in the figure. Initially, by applying horizontal velocity \(v_0\) at the point ‘A’, the string becomes slack when the bob reaches at the point ‘D’. The ratio of the kinetic energy of the bob at the points B and C is: