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Answer: Infrared light</h2>
A dark nebula is a cloud of dust and cold gas, which does not emit visible light and hides the stars it contains.
These types of nebulae are composed mainly of the hydrogen they obtain from nearby stars, which is their fuel.
It is using infrared light that we can "observe" and analyze in detail what happens in the inner parts of these nebulae.
Answer:
Part a)

Part B)
percentage increase is
%
Explanation:
Part a)
As we know that the beat frequency is

after increasing the tension the beat frequency is decreased and hence the tension in string B will increase
So we have


Part B)
percentage increase in the tension of the string will be given as


now we have

so we have


so we have

percentage increase is

The answer is true. I hope that this helps you out!!
Place the next vector with its tail at the previous vector's head. ... To subtract vectors, proceed as if adding the two vectors, but flip the vector to be subtracted across the axes and then join it tail to head as if adding. Adding or subtracting any number of vectors yields a resultant vector.
Explanation:
The kinetic energy will be greatest at the bottom of the swing motion.
The potential energy will be greatest at the highest position of the swing.
Potential energy is the energy stored in an object or system due to the position or placement of its parts. However, it is not affected by the external environment of the object or system. Kinetic energy, on the other hand, is the energy of the particles of an object or system in motion.
In an oscillating pendulum, the potential energy and gravitational kinetic energy are constantly changing. The potential and kinetic energies are maximal at extreme and intermediate positions, respectively.
Learn more about the pendulum in
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