A barometer contains two uniform capillaries of radii `7.2 xx10^-4m` and `1.44 xx10^-3m`. If the height of liquid in narrow tube is 0.2 m more than that in the wide tube, calculate the true pressure difference. Density of liquid = `10^3 kg m^-3`, surface tension = `72 xx 10^-3 N m^-1` and g = `9.8 m s^-2`