A body weighs 30 kg on the surface of the earth how much would it weigh on the surface of a planet whose mass is 1/9 the mass of earth and radius is half of that of earth?
Weight on earth = 30 kg wt = 30 x g N
g on new planet, g’ = GM’/R’2=(4/9)g
Therefor weight on the new planet will be equal to 4/9 times its weight on earth
(Whereas the mass will be the same)
A group of UK Physicists claim that they have developed graphene bubbles which can change its curvature and hence its focal length and power by applying small voltages. If developed, this can be used in mobile cameras and other such devices. This would better imitate the functioning of Human Eye too.
More details available at http://physicsworld.com/cws/article/news/47250