# The space probe Pioneer 11 was launched

The space probe Pioneer 11 was launched April 5, 1973, and reached Jupiter in December 1974, traveling a distance of 998 million km. How long did it take an electromagnetic signal to travel to Earth from Pioneer 11 when it was near Jupiter?

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#### Solution:

To do this question, we must know that electromagnetic signals travel at the same speed as light.

The speed of light = $2.998\times 10^8 \frac{m}{s}$.

Knowing that, we simply have to divide the distance it took for the signal to travel by the speed of electromagnetic signals.

$\dfrac{998\times 10^9\text{m}}{2.998\times 10^8\frac{\text{m}}{\text{s}}}\,=\,3.33\times 10^3$ seconds