Question

The rocket that carried the Curiosity Rover to Mars traveled at a speed of 21,000 miles per hour. What is this speed to the nearest mile per second?
6 miles per second
350 miles per second
1,260,000 miles per second
75,600,000 miles per second

Answer 1

To convert the speed from miles per hour to miles per second, you can use the following conversion:

1 hour = 3600 seconds

Now, divide the speed in miles per hour by the number of seconds in an hour:

\[
\frac{21,000 \text{ miles/hour}}{3600 \text{ seconds/hour}} \approx 5.8333 \text{ miles/second}
\]

Rounding this to the nearest mile per second gives you 6 miles per second.

So the correct answer is **6 miles per second**.