Properties Of Matter

The surface of water in a water tank of cross section area \(750 \mathrm{~cm}^{2}\) on the top of a house is \(h \mathrm{~m}\) above the tap level. The speed of water coming out through the tap of cross section area \(500 \mathrm{~mm}^{2}\) is \(30 \mathrm{~cm} / \mathrm{s}\). At that instant, \(\frac{d h}{d t}\) is \(x \times 10^{-3} \mathrm{~m} / \mathrm{s}\). The value of \(x\) will be ____________.