Answer:
Galileo performed a famous experiment where he used a ball rolling on a ramp (inclined plane) to study the motion of objects under the influence of gravity. The ramp allowed him to make more precise measurements because the ball moved more slowly along the ramp than if it were simply dropped. Galileo discovered through this experiment that the objects fell with the same acceleration, proving his prediction true, while at the same time disproving Aristotle's theory of gravity (which states that objects fall at speed proportional to their mass). Galileo's conclusion from this thought experiment was that no force is needed to keep an object moving with constant velocity. Newton took this as his first law of motion. One result of the experiment surprised Galileo, and one surprises us. Galileo found that the heavy ball hit the ground first, but only by a little bit. Except for a small difference caused by air resistance, both balls reached nearly the same speed. And that surprised him. According to history, Galileo’s experiment on falling bodies largely contributed to Isaac Newton’s Law of Gravity. In Galileo’s experiment, he is said to have dropped balls from the Leaning Tower of Pisa. The balls were made of the same material but had different masses. Galileo set out to prove that the time it took for these objects to reach the ground would be the same. Galileo proved that objects reached the ground at the same time,
Explanation:
I think this is right & I hope this helped
Answer: Most of the stars in the universe are main sequence stars — those converting hydrogen into helium via nuclear fusion. A main sequence star may have a mass between a third to eight times that of the sun and eventually burn through the hydrogen in its core. Over its life, the outward pressure of fusion has balanced against the inward pressure of gravity. Once the fusion stops, gravity takes the lead and compresses the star smaller and tighter.
Temperatures increase with the contraction, eventually reaching levels where helium is able to fuse into carbon. Depending on the mass of the star, the helium burning might be gradual or might begin with an explosive flash.
Neon, Helium, Krypton, Xenon, Argon
Answer:
85.5 mmHg is the pressure of the gas sample when the valve is opened.
Explanation:
The combined gas equation is,

where,
= initial pressure of gas in container A = 165 mmHg
= final pressure of gas = ?
= initial volume of gas in container A= 
= final volume of gas = 135 mL + 117 mL = 252 mL
= initial temperature of gas in container A = 
= final temperature of gas = 
Now put all the given values in the above equation, we get:



85.5 mmHg is the pressure of the gas sample when the valve is opened.
Answer:
Approximately
.
Explanation:
Lookup Avogadro's Number:
(three significant figures.)
Lookup the relative atomic mass of
,
, and
on a modern periodic table:
(For example, the relative atomic mass of
is
means that the mass of one mole of
atoms would be approximately
grams on average.)
The question counted the number of
molecules without using any unit. Avogadro's Number
helps convert the unit of that count to moles.
Each mole of
molecules includes exactly
of these
molecules.
molecules would correspond to
of such molecules.
(Keep more significant figures than required during intermediary steps.)
The formula mass of
gives the mass of each mole of
molecules. The value of the formula mass could be calculated using the relative atomic mass of each element:
.
Calculate the mass of approximately
of
:
.
(Rounded to three significant figures.)