In a Hare's apparatus, the height of water and a liquid X are 0.3m and 0.5m respectively. The relative density of x is?

The quantity of heat required to melt ice of 0.2 kg whose specific latent heat is 3.4 x 10\(^5\)J/Kg is

I  It wets glass

II It needs to be coloured

III It has a low density

Water is not suitable for use as a thermometric liquid because

The power of a convex lens of focal length 20cm is 

The charge of magnitude 1.6 x 10 \(^{-19}\)C is placed in a uniform electric field of intensity 1200Vm\(^{-1}\). Calculate its acceleration, if the mass of the charge is 9.1 x 10\(^{-31}\)kg