Answer:
The electromagnetic waves appear more blue in color.
Explanation:
Doppler's Effect: When a source moves with respect to the observer the frequency of the wave emitted from the source changes. If the source moves away from the observer, the frequency decreases and wavelength increases and vice versa.
Here the light source is moving towards the observer so the frequency will increase and wavelength will decrease. Thus the spectrum will shift towards the blue part. This is known as blue shift. The light wave will appear blue in color.
Answer: The reason for the differences in density is the composition of rock in the plates. When two plates come in contact with each other through plate tectonics, scientists can use the density of the plates to predict what will happen. Whichever plate is more dense will sink, and the less dense plate will float over it.
Explanation:
Hope this helps ( not copied and pasted, this answer was done by me so I don't know if it's good or not)
Answer:
Part a)

Part b)

Part c)

Explanation:
Part a)
As we know that the friction force on two boxes is given as



Now we know by Newton's II law

so we have




Part b)
For block B we know that net force on it will push it forward with same acceleration so we have




Part c)
If Alex push from other side then also the acceleration will be same
So for box B we can say that Net force is given as




The answer is 294j by puting it in kinetic energy formula.
Answer:
Sagittarius A
Explanation:
The center of the milky way has a big giant hole known as "Sagittarius A". The size is 4 million times bigger than the sun.