- 112

- 0

**1. Homework Statement**

A certain star is 76.6 light-years away. How many years would it take a spacecraft traveling 0.946c to reach that star from Earth, as measured by observers on Earth? How many years would it take to reach that star from Earth, as measured by observers on the spacecraft?

**2. Homework Equations**

Relativistic Time = Original Change in Time / sqrt(1 - v/c)^2

**3. The Attempt at a Solution**

For the first question, 1/.946 = 1.057

1.057 * 76.6 light years = 81 years

For the second question, I can't get the right answer. What I did was:

81 / sqrt[1- (.946)^2] and got 250, but that is wrong. not sure what I'm doing wrong...