Answer:
Isotopes
Answer:
The number of neutrons can vary, but not protons. This is called an isotope. An example is deuterium, an isotope of hydrogen with an extra neutron, but the same number of protons.
<h2>Answer: Light waves have a redshift due to the Doppler effect
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The astronomer Edwin Powell Hubble observed several celestial bodies, and when obtaining the spectra of distant galaxies he observed the spectral lines were displaced towards the red (red shift), whereas the nearby galaxies showed a spectrum displaced to the blue.
From there, Hubble deduced that the farther the galaxy is, the more redshifted it is in its spectrum. <u>The same happens with the stars and this phenomenom is known as the Doppler effect.
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This phenomenon refers to the change in a wave perceived frequency (or wavelength=color) when the emitter of the waves, and the receiver (or observer in the case of light) move relative to each other. For example, as a star moves away from the Earth, its espectrum turns towards the red.
Answer:
1.78 s
Explanation:
Initial speed of the ball = u = 7.95 m/s and is vertically downwards.
Acceleration due to gravity = g = 9.8 m/s/s , vertically downwards.
Height of the building h = 29.8 m (traversed downwards by the steel ball).
h = u t + 1/2 g t²
29.8 = 7.95 t + 0.5 (9.8) t²
⇒ 4.9 t² +7.95 t - 29.8 = 0
Using the quadratic formula , solve for t.
t= 
t = 
= 1.78 s, -3.4 s
Since time does not have a negative value, time taken by the stone to reach the ground = t = 1.78 s
Answer:
Inertia
Explanation:
When the planes moves downward a speed, the weight of the person will decrease a bit due to the amount of g decreases for that particular instant. The person is now experiencing a less than actual weight called as apparent weight due to the upward superposition of inertia on the body as we can see in w = m g .
