How Fast is the Alien Spacecraft Flying Overhead?

In summary, the conversation is about calculating the speed of an alien spacecraft based on the duration of a signal light. The commander of the spacecraft measures the signal to be on for 12.0 ms, and the person asking the question calculated the speed to be greater than the speed of light. They were advised to show their work to get a better explanation or to check for any miscalculations. The calculated speed was determined to be 0.998c, making the spacecraft very fast.
  • #1
da_warped_1
7
0
hey i just need a lil help with this question

An alien spacecraft is flying overhead at a great distance as you stand in your backyard. Yyou see a bright signal light in the spaceship blink on for 190.0 ms. The commander of the spacecraft measures that the signal is on for 12.0 ms.

what is the speed of the spacecraft relative to the earth?

i calculated the speed and it comes out to be greater than the speed of light, which is impossible. just wondering if i had calculated it wrong or maybe someone has a better explanation!

thanks
 
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  • #2
Show your work and someone will probably be able to tell you where you went wrong. Otherwise we can only guess!
 
  • #3
i worked it out, just a simple miscalculation.

cheers
 
  • #4
you should get ...

v=0.998c​

So that's a fast vessel.

pess
 

What is time dilation?

Time dilation is a phenomenon in which time appears to pass slower for an object that is moving at high speeds or in a strong gravitational field. This is due to the fact that time is relative and is affected by the speed and gravity of an object.

How does time dilation affect spacecraft?

Time dilation affects spacecraft because they travel at very high speeds and can experience significant gravitational forces. This can cause time to pass slower for astronauts on board the spacecraft compared to someone on Earth, resulting in a difference in the passage of time.

What is the formula for calculating time dilation?

The formula for time dilation is t' = t√(1 - (v^2/c^2)), where t' is the time measured by an observer in a stationary frame, t is the time measured by an observer in a moving frame, v is the relative velocity between the two frames, and c is the speed of light.

Can time dilation be observed on Earth?

Yes, time dilation can be observed on Earth, although the effect is very small. For example, a clock placed at the top of a tall building will run slightly faster than a clock placed at ground level due to the difference in gravitational pull. This phenomenon is known as gravitational time dilation.

How does time dilation impact space travel and exploration?

Time dilation has a significant impact on space travel and exploration as it affects the perception of time for astronauts and the synchronization of clocks between different spacecraft. It also plays a role in planning and coordinating missions that involve communication and navigation over vast distances in space.

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