If a star’s light is shifted to the red part of the light spectrum, that means
that the light waves we see when we look at that star are longer than
they SHOULD be ... longer than they were when they left the star.
Note:
The wavelengths are NOT "getting longer" while we sit there and look
at them. That doesn't happen. They ARE longer than they should be.
Right now, the only way we KNOW OF that can increase the wavelength
of light is if the source of the light is moving AWAY from us, and so we
mark that star down in our notebook, and next to it we write "This star is
moving away from us.". This is kind of what choice-C is trying to say.
The thing about this whole story that should blow our minds is this:
-- We observe a star or a galaxy.
-- The light we observe has wavelengths longer than they should be.
-- We say that the star or galaxy is moving away from us.
Now, my question to you is:
HOW do we know what the wavelengths SHOULD be ? ?
We only know what we see. How do we know what the
wavelength was when the light left the star or galaxy ?
The answer is; 2.
To balance a chemical equation, the moles on one side of the equation has to be the same as that on the other side. This ensures that the law of conservation is observed because matter or energy can't be created or destroyed but can only be transformed from one form to another.
In this equation, putting 2 in front of NaCl ensures that there are 2 moles of Na and CL just as there are 2 moles of Na and CL in the reactants side.
Answer:
c-) both objects will reach the bottom at the same instant.
(b) decrease.
Explanation:
Although the feather is lighter than the coin, the tube where the experiment is performed is evacuated. Therefore there is no air that prevents the feather from falling freely with the same acceleration and speed as the coin.
In fact in the equations of kinematics proposed by Newton, the mass of the bodies is not taken into account, as we can see in the following equation:
where:
Vf = final velocity [m/s]
Vi = initial velocity [m/s]
g = gravity acceleration [m/s^2]
t = time [s]
Therefore the answer is C.
Gravitational pull is a function of height, as the height of the body increases, the force of gravity decreases.
Answer:
Its final velocity and how much time it takes to reach the water
Explanation:
The motion of the stone is a uniformly accelerated motion, so we can use the following suvat equation to determine its final velocity:
where
v is the final velocity
u = 0 is the initial velocity
is the acceleration of gravity
s = 52 m is the distance covered during the fall
Solving for v,
We can also find how much time it takes to reach the water, using the equation
where
v = 31.9 m/s is the final velocity
u = 0 is the initial velocity
t is the time
And solving for t,