Determine the number of years that have passed on the earth if 12 years have passed in the spacecraft

Determine the number of years that have passed on the earth if 12 years have passed in the spacecraft at a speed of its movement relative to the earth equal to 0.80 s.

To find out the required time elapsed on Earth, we use the formula: t = t0 / √ (1 – Vk ^ 2 / C ^ 2), where t0 is the time elapsed on the presented spacecraft (t0 = 12 years); Vk is the speed of the spacecraft (Vk = 0.8C).

Let’s perform the calculation: t = t0 / √ (1 – Vk ^ 2 / C ^ 2) = 12 / √ (1 – (0.8C) ^ 2 / C ^ 2) = 12 / √0.36 = 20 years.

Answer: On Earth, according to the calculation, 20 years have passed.