Posted by **julie** on Friday, August 10, 2012 at 8:11pm.

A passenger on an interplanetary express bus traveling at = 0.95 takes a 9.0-minute catnap, according to her watch.How long does her catnap from the vantage point of a fixed planet last?

- physics (Relativity) -
**drwls**, Friday, August 10, 2012 at 10:21pm
You need to tell us what the units of velocity are. I assume that the "bus" is travelling at 0.95c, or 95% of the speed of light, with respect to a "fixed" planet - presumably the home planet where the passenger came from.

Someone is apparently trying to teach you the theory of relativity. That person should know that it is measingless to say something is "fixed" unless a frame of reference is specified.

You need to use the "time dilation" formula of Special Relativity. It is probably explained in your textbook or class notes. A tutorial on the subject can easily be found with Google.

The nine minute time interval measured on the watch of the traveler will appear longer on the planet, by a factor

1/sqrt[1 - (0.95)^2] = 3.20

That means the nap will be 28.8 minutes long as measured on the home planet.

## Answer This Question

## Related Questions

- Physics Help!! - A passenger on an interplanetary express bus traveling at v = 0...
- Physics Help please - A bus moving with speed 0.93c is 65 feet long according to...
- Algebra 2 word problem - Just wanted to check to see if these are correct. Thank...
- physics - A passenger on a stopped bus notices that rain is falling vertically ...
- probability help!! - buses arrive at a bus stop at 15minute interval,starting ...
- Physics - how many revolutions per minute would a 5.8 metre radius ferris wheel ...
- math - 5. A bus on a regular schedule takes 3 1/4 hours to reach its ...
- Math - 5) A freight train leaves a station traveling at 32 km/h. Two hours later...
- Math - The bus stations in Trawlwy and Fenton are 220 miles apart. A bus left ...
- Algebra - The bus stations in Trawlwy and Fenton are 220 miles apart. A bus left...

More Related Questions