Answer: The star is moving away from Earth
Explanation:
Let's begin by explaining what the Doppler shift is:
This is related to the Doppler effect and refers to the change in a wave perceived frequency (or wavelength=color) when the emitter of the waves, and the observer move relative to each other.
From there, it is deduced that the farther the object is, the more redshifted it is in its spectrum. For example, as a star moves away from the Earth, its espectrum turns towards the <u>red</u> and as the star moves toward the Earth, its espectrum turns towards the <u>blue</u>.
In this sense, since the peak in wavelength is around 650 nm, which corresponds to red, it can be said the star is moving away from Earth.
Answer:
Velocity (magnitude) is 98.37 m/s
Explanation:
We use the vertical component of the initial velocity, which is:
Using kinematics expression of vertical velocity (in y direction) for an accelerated motion (constant acceleration, which is gravity):
Now we need to find 
as a function of 
. We use the horizontal velocity, which is always the same as follow:
We know the angle at 3 seconds:
Substitute 
in 
and then solve for
With this expression we go back to the kinematic equation and solve it for initial speed
