Question

Summarize two observations that are contrary to the predictions based on Newton’s laws but that confirm Einstein’s explanation of gravity. Indicate how the predictions based on Newton’s theory differ from Einstein’s.

Answer 1

I can only think of one. There's a thought experiment about how the planets would act if the sun suddenly disappeared. Based on Newton's laws, the planets would start moving away from the solar system the instant that the sun disappears because there won't be anymore mass that would hold it in orbit. However, according to Einstein's theory of relativity (which basically explaines gravity), there will be a lag time before the planets start moving away from their orbit. This is because Einstein's explanation of gravity depends on the structure of space and time.

Answer 2

The planets in our system, I mean.

Answer 3

The LINEAR ACCELERATOR is one in which charged particles such as protons are accelerated to very very high velocities. On Newton's theory, the particles should just get faster and faster and faster and faster. But, it is found that the particles actually go asymptotically to c, the speed of light.
Their mass-energy increases, and it becomes "harder" to accelerate them. In that sense they "gain" mass.
MIT did a video experiment/demonstration of the decay of mesons at the top of Mount Washington, and compared it to the decay of mesons (small value of half life) at the bottom of the Mt. They argued that their results demonstrated relativistic time dilation and length contraction. The expt is reported in "Special Relativity" by AP French of MIT.

Answer 4

there is also the description of mercury's orbit around the sun which Einstein regarded as a vital test of general relativity, and there is gravitational lensing featuring the cassini thing.