Question

a planet makes 15 orbits in 60 days, what is the period of the planet is seconds?
a 4 s
b 2.2×10⁴ s
c 3.5×10⁵ s
d 6.5×10⁷ s

Explanation:

Step1: Calculate the time for one orbit in days

The planet makes 15 orbits in 60 days. So the time for one orbit \(T_d\) (in days) is \(\frac{60}{15}=4\) days.

Step2: Convert days to seconds

We know that 1 day = 24 hours, 1 hour = 60 minutes and 1 minute = 60 seconds. So 1 day \(=24\times60\times60 = 86400\) seconds.
If \(T_d = 4\) days, then \(T_s=4\times86400\) seconds.
\(T_s=4\times8.64\times10^{4}=3.456\times10^{5}\approx3.5\times 10^{5}\) seconds.

Answer:

C. \(3.5\times10^{5}\text{ s}\)