can we over come the gravitational force?
Its highly difficult to over come the gravitational force even in the space also.since if we go to the moon there exists the attractions of earth,sun and if we go beyond the solar system there exists the attractions of milky way galaxies and if we go beyond this milky way galaxy there exists Andromeda galaxies attraction and this continues up to the   nebules,clusters clustergroups,massive stars etc.....there fore we cannot overcome the gravity at any section in universe but up to some extent we can.. over come the gravity on earth itself!

How? By the 1.huge rotation(centrifuge process(or)gyroscopic persession) and 
By 2.heavy reaction towards the earth(according to newton's third law:for every action there is equal and opposite reaction)
by the usage of the two forces we can over come the gravitational forces on earth itself ...

       we cannot lift that one with out rotation because of gravity.but we can by gyroscopic persession .and this video gives that how we can overcome the gravity by centrifuge(heavy rotation)...and the second repelling force of gravity is given through the example of rockets...
In which the fuel in the rockets hits the ground with a high speed which gives the reaction to the rocket which should move upwards with a high speed of 11.2 km/s..at this high reaction towards earth leads the rocket into the space.
so we can clearly say that we can overcome the gravity upto some extent only.....
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