A supertrain of proper length 190 m travels at a speed of 0.9c as it passes through a tunnel having proper length 90 m. How much longer is the tunnel than the train or vice versa as seen by an observer at rest with respect to the tunnel?
the answer is in meters
2007-11-20 13:00:38 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Physics
The observer in the tunnel rest frame will see the train's length reduced by the Lorentz factor, usually expressed using the Greek letter gamma:
gamma = 1 / sqrt ( 1 - v^2 / c^2 )
which you can compute as you know that v = .9c
The observed length of the train = proper length * gamma
2007-11-20 13:06:57 · answer #1 · answered by jgoulden 7 · 1⤊ 0⤋
Take the north course as x- axis and east as y-axis. Then the preliminary speed is 50i and last speed is -50j. The difference in speed = -50j-50i. So, while you'll plot it within the co-ordinate axis it's alongside south- west. The importance is 70 as you could have already guessed. (P. S. - i and j are unit vectors alongside x and y -axis)
2016-09-05 10:40:00 · answer #2 · answered by Anonymous · 0⤊ 0⤋