Someone in Earth's Rest Frame Says That a Spaceship's Trip

question 32

Multiple Choice

Someone in Earth's rest frame says that a spaceship's trip between two planets took 10.0 y, while an astronaut on the space ship says that the trip took 6.27 y. Find the speed of the spaceship in terms of the speed of light.

• A) 0.779c
• B) 0.687c
• C) 0.975c
• D) 0.384c

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Definitions:

After-tax Real Rate

The actual income rate of return on an investment, after accounting for inflation and taxes.

After-tax Real Rate

The after-tax real rate is the interest rate that remains after adjusting for both taxes and inflation, showing the real earning power of money over time.

Real Interest Rate

The effective interest rate once inflation is considered, showcasing the authentic expense of borrowing and the legitimate earnings for investors.

Marginal Tax Rate

The rate at which the next dollar of taxable income is taxed, indicating the tax impact on an additional unit of income.