Answer:
1.63103 seconds
Explanation:
[tex]\Delta t[/tex] = Actual period of clock = 1 second
v = Speed at which the observer is moving = 0.79 c
c = Speed of light = [tex]3\times 10^8\ m/s[/tex]
Time dilation is given by
[tex]\Delta t'=\frac{\Delta t}{\sqrt{1-\frac{v^2}{c^2}}}\\\Rightarrow \Delta t'=\frac{1}{\sqrt{1-\frac{0.79^2c^2}{c^2}}}\\\Rightarrow \Delta t'=1.63103\ s[/tex]
The period is 1.63103 seconds