<span>Hydrogen
gas (H2) can be found in trace amounts in Earth’s atmosphere.
a. Hydrogen is found in acids.
b. Hydrogen gas is highly flammable.
c. Hydrogen reacts with oxygen to form water.
These are true, but they all describe chemical properties
of Hydrogen, not physical properties.
d. Hydrogen gas
is less dense than oxygen gas.
Yes ! This is a physical property of Hydrogen.
</span>
Alex is driving at 21.2508882 miles per hour
B) <span> It is practical because a top-loading machine uses much more water than a front-loading machine.
Front-loading washing machines are able to better conserve water by automatically maintaining the same water level throughout the wash, while top-loading washing machines generally begin the cycle by filling up the barrel to a certain point. </span>
Answer:
high density can withstand high acceleration and applied forces
Heavy metals are toxic to humans,
the clay is quite abundant and in general it is not toxic
Explanation:
The selection of materials for the construction of rockets takes into account many aspects, the technical resistance to the demands of space travel, but also the abundance of the material. Heavy metals have two very serious problems. The first one, some of them are a little scarce in nature, but the most serious problem is that almost all of them are toxic to humans, for example: lead and mercury.
On the other hand, the clay is quite abundant and in general it is not toxic to living beings.
If we use Newton's second law
F = m a
let's use the concept of density
rho = m / V
m = rho V
let's substitute
F = rho V a
From this expression we see that a material with high density can withstand high acceleration and applied forces, such as those existing in spacecraft clearance and re-entry to Earth.
Unfortunately with this law there is no criterion to select a material unless its density is high, in addition to this criterion low toxicity criteria for human beings are used,
