The color of light that a star emits is somewhat related to its age, whereas the color of light that we actually <em>observe</em> from a star is related to the speed at which it's moving with respect to us.
Answer:

Explanation:
The motion of ballistic pendulum is modelled by the appropriate use of the Principle of Energy Conservation:

The final velocity of the system formed by the ballistic pendulum and the bullet is:



Initial velocity of the bullet can be calculated from the expression derived of the Principle of Momentum:


<span>Answer: "a cold front" .
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Answer:
We kindly invite you to read carefully the explanation and check the image attached below.
Explanation:
According to this problem, the rocket is accelerated uniformly due to thrust during 30 seconds and after that is decelerated due to gravity. The velocity as function of initial velocity, acceleration and time is:
(1)
Where:
- Initial velocity, measured in meters per second.
- Final velocity, measured in meters per second.
- Acceleration, measured in meters per square second.
- Initial time, measured in seconds.
- Final time, measured in seconds.
Now we obtain the kinematic equations for thrust and free fall stages:
Thrust (
,
,
,
)
(2)
Free fall (
,
,
,
)
(3)
Now we created the graph speed-time, which can be seen below.