The answer is D. Isotopes.
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Answer:
La velocidad es una magnitud física que expresa la relación entre el espacio recorrido por un objeto, el tiempo empleado para ello y su dirección. ... Su unidad en el Sistema Internacional de Unidades es el metro por segundo (m/s), e incluye la dirección del desplazamiento
Explanation:
Explanation:
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If a star is moving towards Earth, shift towards the blue end of the spectrum, this is called blue shift. If the star is moving away from Earth the light from that star will be red and is called red shift .
The faster a star moves towards the earth, the more its light is shifted to higher frequencies. In contrast, if a star is moving away from the earth, its light is shifted to lower frequencies on the color spectrum
if a star is moving towards Earth, it appears to emit light that is shorter in wavelength compared to a source of light that isn't moving. Because shorter wavelengths correspond to a shift towards the blue end of the spectrum, this is called blue shift.
If the star is moving away from Earth, its light will lose energy to reach Earth, therefore the light from that star will be red and is called red shift
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