A) 600 km/s
B) 800 km/s
C) 1500 km/s
D) 1200 km/s
Correct Answer: D
Solution :
For Doppler effect in light, \[f={{f}_{0}}\sqrt{\frac{1-v/c}{1+v/c}}\] \[\Rightarrow \]\[\frac{c}{\lambda }=\frac{c}{{{\lambda }_{0}}}\sqrt{\frac{1-v/c}{1+v/c}}\] \[\Rightarrow \]\[\frac{\lambda }{{{\lambda }_{0}}}={{\left[ \frac{1+v/c}{1-v/c} \right]}^{1/2}}=\frac{1+2v/c}{1-2v/c}\] \[[v<<]\] \[\Rightarrow \]\[\frac{\lambda -\lambda }{{{\lambda }_{0}}}=\frac{\text{ }\!\!%\!\!\text{ }\,\text{change}\,\text{in}\,\text{wavelength}}{\text{100}}=\frac{v}{c}\] \[\Rightarrow \]\[v=1200\,km/s\]
You need to login to perform this action.
You will be redirected in
3 sec
