Suppose there are two twins, Greg and Sam. Greg stays on Earth and Sam travels to the stars as a scientist. Space travel has advanced to the point where spaceships can travel through the universe at speeds close to the speed of light. When Sam returns to Earth, how would the twins’ ages compare?

a. sam would be older
b. sam would be younger
c. sam and greg would be the same age

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.

the temperature in kelvin of 2.0 dm3 of an ideal gas is doubled and its pressure is increased by a factor of four. what is the final volume of the gas

answer: 31, 5556. 952 seconds