Question

The pressure at a point in water is 10 N/m squre .the depth below this point where the presure becomes double is (given density of water = 10 cube kg/m cube ,g= 10 m/s square ?????????????????????????????????

Answer 1

The pressure at a point in water is $10\ \mathrm{N/m}$ square. The depth below this point where the pressure becomes double is (given density of water = 10 cube kg/m cube, g = 10 m/s square?)

**Solution:**

$$p_1 = 10 \frac{\mathrm{N}}{\mathrm{m}^2} - \text{pressure at the first point}$$ $$p_2 = 2p_1 - \text{pressure at the second point};$$

Formula for the pressure:

$$p_1 = \rho g h_1$$ $$p_2 = \rho g h_2 = \rho g (h_1 + \Delta h) = \rho g h_1 + \rho g \Delta h$$ $$p_2 = 2p_1 \Rightarrow$$ $$p_1 + \rho g \Delta h = 2p_1$$ $$p_1 = \rho g \Delta h$$ $$\Delta h = \frac{p_1}{\rho g} = \frac{10 \frac{\mathrm{N}}{\mathrm{m}^2}}{1000 \frac{\mathrm{kg}}{\mathrm{m}^3} \cdot 10 \frac{\mathrm{N}}{\mathrm{kg}}} = 1\ \mathrm{mm}$$

**Answer:** the depth below this point where the pressure becomes double is $1\ \mathrm{mm}$.