<p>A ball of mass 100 g is dropped from a height h = 10 cm on a platform fixed at the top of a vertical spring (as shown in figure). The ball stays on the platform and the platform is depressed by a distance&nbsp;<span class="equation">\(\frac{h}{2}\)</span>. The spring constant is ___________<span class="equation">\(Nm^{-1}\)</span>.​​​​​​​​​​​​​​</p>

<p>(use g = 10&nbsp;<span class="equation">\(ms^{-2}\)</span>)</p>

<p><img alt="" src="https://school.achievam.com/upload/questionbank/question/que_1759483204.png" style="height:120px; width:119px" />​​​​​​​</p>