Chapter 37, Problem 37.51P

Everyday Time Dilation. Two atomic clocks are carefully synchronized. One remains in New York, and the other is loaded on an airliner that travels at an average speed of 250 m/s and then returns to New York. When the plane returns, the elapsed time on the clock that stayed behind is 4.00 h. By how much will the readings of the two clocks differ, and which clock will show the shorter elapsed time? (Hint: Since u ≪ c, you can simplify $\sqrt{1-u^2/c^2}$ by a binomial expansion.)