Energy \(=90 \,J \quad\) Amplitude \(=6 \,cm\)
Maximum energy \(=\frac{1}{2} m A^2 \omega^2=90\)
\(\text { or } m \omega^2=\frac{180}{36 \times 10^{-4}}\)
\(\therefore m \omega^2=30 \times 10^2\)
When particle is stopped the point where it is stopped is the new amplitude but angular velocity will remain same.
\(E=\frac{1}{2} m A_2^2 \omega^2\)
\(\text { or } E=3000 A_2^2\)
\(A_2=4 \times 10^{-2}\)
\(A_2=3000\)
($g = 10\,m/s^2$ અને ગતિ દરમિયાન સ્પ્રિંગ વિકૃત થતી નથી)