Saved Bookmarks
| 1. |
The velocity of a moving galaxy is 300 km s^(-1) and the apparent change in wavelength of a spectral line emitted from the galaxy is observed as 0.5 nm. Then, the actual wavelength of the spectral line is |
|
Answer» `3000 Å` `v = 300 kms^(-1) = 300 xx 10^(3) ms^(-1)` As `(Deltalambda)/(lambda) = (v)/(c) rightarrow = lambda = (Deltalambda c)/(v)` `therefore lambda = (0.5 xx 10^(-9)m)(3 xx 10^(8) ms^(-1))/(300 xx 10^(3)ms^(-1)) = 5 xx 10^(-7) m` `= 5000 xx 10^(-10) m = 5000 Å`. |
|