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lakshmi
Aug17-04, 10:56 AM
what is the value of 1 light year

pmb_phy
Aug17-04, 11:17 AM
what is the value of 1 light year
It is the distance light travels in one year. It, in itself, is a measure of distance so perhaps you're interested in converting this to meters? Miles?

Pete

GOD__AM
Aug17-04, 12:25 PM
It is the distance light travels in one year. It, in itself, is a measure of distance so perhaps you're interested in converting this to meters? Miles?

Pete

A measure of distance? How can light speed be an accurate measure of distance when it travels with respect to an observer?

Nereid
Aug17-04, 12:31 PM
A measure of distance? How can light speed be an accurate measure of distance when it travels with respect to an observer?'distance' as in 'within your own frame of reference' (or one not in relative motion to yours); to obtain a value for the distance as observed by someone in a different frame, just apply Relativity!

decibel
Aug17-04, 12:40 PM
The valua at which light travels in a year is approx. 9,500,000,000,000 kilometers.

pmb_phy
Aug17-04, 12:41 PM
A measure of distance? How can light speed be an accurate measure of distance when it travels with respect to an observer?
Because the speed of light is independant of the observer. Therefore since all observers measure the same speed of light, 1 light year is a well defined quantity (although different observers measure different distances between events, but that's a whole different topic).

Pete

Nenad
Aug17-04, 01:42 PM
Here is the full Calculation:
v=\frac{d}{t}

d=vt
d=cy

d=(3.0*10^8\frac{m}{s})(3.15*10^7\frac{s}{year})(\ frac{1km}{1000m})

d= 9 460 800 000 000km

Prometheus
Aug17-04, 01:56 PM
The valua at which light travels in a year is approx. 9,500,000,000,000 kilometers.
I think that you are taking liberties with the meaning of the word value.

pervect
Aug17-04, 07:28 PM
A measure of distance? How can light speed be an accurate measure of distance when it travels with respect to an observer?

Take a look at the defintion of the SI meter sometime

robphy
Aug17-04, 10:13 PM
Here's a nice order of magnitude calculation. (No calculators needed.)

1\ yr \approx \pi\times 10^7\ s
c \approx 3\times 10^8\ m/s

1\ light\ yr=(c)(1\ yr) \approx (\pi\times 10^7\ s)(3\times 10^8\ m/s)=3\pi \times 10^{15}\ m

You can work out the analogous approximation in feet using
c \approx 1\ ft/ns