A vector would be a quantity that has both magnitude and direction.
Answer:
c. testing student opinions
Explanation:
opinions aren't factual and they would not aide an experiment if it wasn't for a social experiment.
Answer:
By observing the color of lines in the spectrum.
Explanation:
There are two types of lines in the spectrum explained below:
i) Bright lines: Bright lines occurs on the spectrum when atoms emit photons. These bright lines show the emission line spectrum.
ii) Dark Lines: Dark lines occurs on the spectrum when atoms absorb photons. These black lines show the absorption line spectrum.
Hence, by observing the color of lines it is possible to identify emission line spectrum and absorption line spectrum.
The magnitude of the initial velocity of the ball relative to the ground is 9.3 m/s.
<h3>What is relative velocity?</h3>
Relative velocity is the velocity of an object relative to another moving in the same plane. On frame of reference is used when measuring relative velocity.
The velocity of the ball relative to the ground is the sum of the velocity of the ballistic cart and the velocity in which the ball is ejected.
The velocity of the ball relative to the ground = 6.5 m/s + 2.8 m/s = 9.3 m/s
In conclusion, relative velocity measures the velocity of an object from a reference point.
Learn more about relative velocity at: brainly.com/question/24337516
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