More cool stars produce much of their light in the red part of the spectrum, so you see them, and bam, the color red. More hot stars, however, produce much more of their light in the green and or yellow spectrums, with much more tinier amounts of red / blue. This balance of the colors, your eye, sees simply as white. The more hot something is, the greater frequency of radiation it produces! Blue light has a higher frequency than red light, so the stars that glow red are cooler, than the stars that glow blue. :)
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Answer:
at point F
Explanation:
To know the point in which the pendulum has the greatest potential energy you can assume that the zero reference of the gravitational energy (it is mandatory to define it) is at the bottom of the pendulum.
Then, when the pendulum reaches it maximum height in its motion the gravitational potential energy is
U = mgh
m: mass of the pendulum
g: gravitational constant
The greatest value is obtained when the pendulum reaches y=h
Furthermore, at this point the pendulum stops to come back in ts motion and then the speed is zero, and so, the kinetic energy (K=1/mv^2=0).
A) answer, at point F