<span>the color of a star is primarily determined by its : suface temperature.
The surface temperature is used to estimate the wavelength that radiated within.
the star with lower wavelegth tend to have purple-ish color, while the one with higher wavelength tend to have orange-ish color</span>
Answer:

Explanation:
The electrostatic attraction between the nucleus and the electron is given by:
(1)
where
k is the Coulomb's constant
Ze is the charge of the nucleus
e is the charge of the electron
r is the distance between the electron and the nucleus
This electrostatic attraction provides the centripetal force that keeps the electron in circular motion, which is given by:
(2)
where
m is the mass of the electron
v is the speed of the electron
Combining the two equations (1) and (2), we find

And solving for v, we find an expression for the speed of the electron:

Responder:
T = 0.25 segundos
f = 4 Hz
Explicación:
Paso uno:
datos dados
se nos dice que las partículas tardan 0,25 segundos en completar una vibración
por lo tanto, el período es de 0,25 segundos
¿Qué es un período de vibración?
Un período T es el tiempo necesario para que un ciclo completo de vibración pase por un punto determinado.
la expresión para el período se da a continuación.
T = 1 / f
¿Cuál es la frecuencia de vibración?
Básicamente, se refiere a la frecuencia con la que ocurren las vibraciones.
la frecuencia es una tasa, se expresa como la inversa del período
f = 1 / T
t = 1 / 0.25
f = 4 Hz
Answer:
P = 96 J
Explanation:
Given that,
Weight of the book, W = mg = 8 N
It is placed at a height of 12 m
We need to find the potential energy of the book. The potential energy of an object is given by the formula as follows :
E = mgh
mg = Weight

So, the potential energy of the book is 96 J.
Answer:
Explanation:
Initial velocity is 0. In the equation v = v0+at where v0 is the initial velocity of 0, we only have to fill in -9.8 for a and 2 for t to get the velocity after 2 seconds -19.6 m/s; after 5 seconds, when it hits the ground, a = -9.8 and t = 5 to give a velocity of -49 m/s. Gravity pulls down everything at the same rate, it doesn't matter whether we drop a feather or an elephant from the window!