Astronaut Mark Uri Is Space-Traveling from Planet X to Planet

question 48

Multiple Choice

Astronaut Mark Uri is space-traveling from planet X to planet Y at a speed of 0.65c relative to the planets, which are at rest relative to each other. When he is precisely halfway between the planets, a distance of 1.0 light-hour from each one as measured in the planet frame, nuclear devices are detonated on both planets. The explosions are simultaneous in Mark's frame. What is the difference in the time of arrival of the flashes from the explosions as observed by Mark?

• A) 0 min
• B) 180 min
• C) 90 min
• D) 360 min
• E) 113 min

---

Definitions:

Economic Profit

The difference between total revenues and total costs, including both explicit and implicit costs, measuring the financial success of a business beyond normal profit margins.

Explicit Costs

Refers to direct monetary expenses businesses incur in their operations, such as wages, rent, and materials.

Normal Profit

Normal profit is the minimum amount of profit needed for a company to remain competitive in the market, covering all its opportunity costs.

Normal Profits

The level of profit that business owners consider satisfactory or "normal", essentially covering both explicit and implicit costs, including a normal rate of return on investment.