Reaching Alpha Centauri in 100 Years: Calculating Speed & Magnitude

AI Thread Summary
To reach Alpha Centauri in 100 years, one must calculate the required speed by determining the distance in kilometers, which is approximately 4.36 light years, and converting that distance into kilometers. The necessary speed is calculated by dividing this distance by the total hours in 100 years. This speed significantly exceeds the capabilities of current spacecraft, which travel at around 50,000 km/hr. By dividing the calculated speed by the speed of current spacecraft, one can determine how many times faster the required speed is. Ultimately, reaching Alpha Centauri in a century demands speeds that are a substantial fraction of the speed of light.
lifeunderwate
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Suppose you wanted to reach Alpha Centauri in
100 years.
a. How fast would you have to go, in km/hr3
b. How many times faster is the speed you found in (a) than
the speeds ofour fastest current spacecraft (around
50,000 km/hr)?
 
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lifeunderwate said:
Suppose you wanted to reach Alpha Centauri in
100 years.
a. How fast would you have to go, in km/hr3
A.Centauri is how far away in light years?
How many km are in a light year?
Multiply and you'll get the distance to A.Centauri in km.

100 years is how many hours?

Speed (in km/hr) to A.Centauri = distance (in km) / time (in hours)


Speed is distance divided by time.

lifeunderwate said:
b. How many times faster is the speed you found in (a) than
the speeds ofour fastest current spacecraft (around
50,000 km/hr)?
Even easier.

You have a speed above, and this comparson speed. Pretty straightforward to divide one by the other.

Why do you need us?
 
Last edited:
Even easier. Take the distance to Alpha Centauri - 4.36 light years - and divide by 100 years. That's the fraction of lightspeed you want. Then multiply by the speed of light per hour. Since light moves at 299792458 m/s, by definition, I'll let you work out km/h...
 
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