Mission Control sends a brief wake-up call to astronauts in a distant spaceship. Five seconds after the call is sent, Mission Control hears the waking groans of the astronauts. How far away at most) from Earth is the spaceship? A) 7.5 × 10⁸ m B) 15 × 10⁸ m C) 30 × 10⁸ m D) 45 × 10⁸ m E) The spaceship is on the Moon.

Question

Quizplus · Accepted Answer

The speed of light (and radio waves) is approximately 3 × 10^8 m/s. If the round trip time is 5 seconds, the one-way distance is 2.5 seconds. Thus, the distance is 2.5 × 3 × 10^8 m = 7.5 × 10^8 m.

Mission Control Sends a Brief Wake-Up Call to Astronauts in a Distant