What two measurements will two observers in relative motion always agree on?
The two measurement will two observers in relative motion always agree on.
Answer to Problem 1Q
The two measurements will two observers in the relative motion always agree on the speed of light and the relative speed between them.
Explanation of Solution
The speed of light in the universe is independent of the velocity of the observer, no matter how the observer moves relative to the light source. It is a universal constant. No information can travel faster than the speed of light. Thus, the speed of light measured by both the observers who are in relative motion is same.
The relative speed between the two observers will be same. Therefore, they agree about their own relative speed.
Conclusion:
Therefore, the two measurements will two observers in the relative motion always agree on the speed of light and the relative speed between them.
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Chapter 1 Solutions
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