Answer:
b) The star is moving away from us.
Explanation:
If an object moves toward us, the light waves it emits are compressed - the wavelength of the light will be shorter, making the light bluer. On the other hand, if an object moves away from us, the light waves are stretched, making it redder. If from laboratory measurements we know that a specific hydrogen spectral line appears at the wavelength of 121.6 nanometers (nm) and the spectrum of a particular star shows the same hydrogen line appearing at the wavelength of 121.8 nm, we can conclude that the star is moving away from npos, since the wavelength related to that star is more expanded.
Answer:
a) 
b) 
c) 
Explanation:
Given masses:


Velocity of mass 1, 
Velocity of mass 2, 
a)
Initial momentum:



b)
magnitude of initial momentum:


From the conservation of momentum:



is the magnitude of final velocity.
Direction of final velocity will be in the direction of momentum:




c)
Vertical component of final velocity:

