Question

In a two-page paper, identify the physics principles contained within the following scenario. Explain how these principals connect to Einstein's theory of relativity or in modern applications in physics. If you use a GPS option on your car or a mobile device, you are using Einstein's theory of relativity. Finally, provide another example from your own experience, then compare and contrast your scenario to the provided example below.

Scenario:

Mandy took a trip to Rome, Italy. She gazed out over the open ocean 20,000 feet below as her airplane began its descent to her final destination of Rome. It had been a long flight from New York to Rome, but she as she stretched, and her bones creaked as though she was old, she knew that in fact, she was a tiny bit younger than her compatriots back home, thanks to traveling at hundreds of miles per hour. In fact, time for her was running slowly compared to her friends in New York for two reasons: the speed at which she had traveled and the height of the airplane above the Earth. Neither, though, were noticeable.

Answer 1

• Special Theory Relativity says that when we move very fast (compared to the fraction of speed of light), because of time dilation effect, clock will run slow for us.

• General Relativity says , if gravitational acceleration is small,then clock will run faster which is a direct contrast to the special theory of relativity.

Explaining GPS with above two facts:

GPS satellites are located almost 20,000 km from earth where gravity is much weaker than the surface of the earth ,hence due to the effect of general relativity satellite clocks run +45 microseconds/day faster daily.

Again GPS satellites are rotating with a speed around 14,000 km/hr, because of this high speed, special relativity comes into play,and due to the time dilation satellite clocks run -7 microseconds /day slower daily.

Now, combining these two effects of relativity, we have that satellite clock would run (45-7) ms/day = +38 ms/day faster daily. To correct this error ,atomic clocks are adjusted to compensate this relativistic effect .

Explaining Scenario 2 with above two facts:

Since Mandy traveled 20,000 feet = 6.096 km above the surface of the earth where gravity was weaker than on the surface. So, because of general relativity time for her run faster ,in other words she has aged quickly. But since she was flying with great speed with the plane, because of the time dilation of special relativity time for her run slower. Hence in a combined effect her age remains the same.