Question

1) How did Einstein show that Newton’s Law of Gravity had a flaw? Did it make Newton’s work useless? Why or why not?

Answer 1

Einstein Hypothesis replaces Newton's law of gravity.

Acconding to Einstein, there is nothing like a gravitational force, instead the presence of a mass causes a space time curvature in its vicinity and all freely moving objects must follow this space time path.

For example whentwo persons start on paralle lines from the equator, by the time they rech the poles the come to the same point though each one thinks they are moving in prallel paths. it is the space time path caused by the presence of earth mass.

Einstein Hypothesis makes newton gravitatinal law more generic and a different way of expressing. it still holds good and works for all pratical puposes.