List and explain brietfly two bits of experimental evidence that support the special theory of relativity.

Numerous experiments have been performed since the formulation of theory of relativity which establish the theory of special relativity, however we shall consider only 2 experiments mentioned below.

1)  Michelson Morley experiment:- Since the basic premise of Newtonian mechanics is that motion of two bodies is always relative and there is no absolute speed of an object, the space was thought to be filled with a special material termed as ether that was supposedly present everywhere and since light was supposed to be as a wave, the speed of light was   thought to be measured with respect to this imaginary substance that was thought to be invisible. By measuring the difference in the speeds of light when moving in the direction of ether and while moving against  the direction of ether would establish the existence of this invisible substance that was thought to be absolute frame of reference of the universe. Michelson Morley used an instrument known as interferometer to measure this difference of speed of light when moving in 2 different directions by making interference patterns of the light when superimposed. The results of the experiment were shocking as no interference patterns were observed thus demolishing the existence of ether and establishing the fact that speed of light is same in all reference frames, a very basic postulate of special theory of relativity.

2) Decay of muons: A basic result that follows from special theory of relativity is that as a object moves faster the time it observes is slower a concept known as time dilatation. This was established by the presence of muons which are elementary particles which are unstable in the lower layer's of atmosphere. Classically the muons should not reach the lower layer's of atmosphere and should decay earlier but as they are observed in the lower layer's of atmosphere because they travel at speeds comparable to speed of light thus the time from a frame attached to muons runs at a slower rate thus giving them time to reach lower region's of atmosphere.

3) GPS systems have been designed taking into effect the calculations predicted by special; theory of relativity.

the word that best describes martin luther king jr.'s tone in the video is dignified

martin luther king, jr. was a social activist and baptist minister who played a key role in the american civil rights movement from the mid-1950s until his assassination in 1968. the video shows his manner and attitude having or showing a composed or serious manner that is worthy of respect so dignified is the correct answer