As shown in Table 24.1, water has a very large dielectric constant ?K ?= 80.4. Why do you think water is not commonly used as a dielectric in capacitors?
Introduction We have to discuss why we don’t use water as dielectric medium in capacitor even though the dielectric constant of water is very high. Step 1 The dielectric constant that is shown in the table is for pure water. It is very difficult to have pure water. In general water contains lots of different salts dissolved in it, which increases the ions in the water and the water become very good conductor of electricity. Also even if we use a pure water, it will absorb ions from the surrounding environment and from the material of the capacitor and it will become conductor. Now, since water becomes conductor, it can not be used as a dielectric medium in capacitor.