Q25. A particle of mass 0.50 kg executes simple harmonic motion under force $F = - 50 \left( \mathrm { Nm } ^ { - 1 } \right) x$. The time period of oscillation is $\frac { x } { 35 } \mathrm {~s}$. The value of $x$ is $\_\_\_\_$ (Given $\pi = \frac { 22 } { 7 }$ )