Answer:
a) fr = 266.92 N, fy = 1300 N, b) μ = 0.36
Explanation:
a) This is a balancing act.
Let's write the rotational equilibrium relations, where the turning point is the bottom of the ladder and the counterclockwise rotations are positive
-w x - W x₂ + R y = 0 (1)
usemso trigonometry to find distances
cos 60.08 = x / 7.5
x = 7.5 cos 60.08
x = 3.74 m
fireman
cos 60.08 = x₂ / 4
x2 = 4 cos 60
x2 = 2 m
wall support
sin 60.08 = y / 15
y = 15 are 60.08
y = 13 m
we substitute in equation 1
R y = w x + W x2
R = (w x + W x2) / y
R = (500 3.74 +800 2) / 13
R = 266.92 N
now let's write the expressions for the translational equilibrium
X axis
R -fr = 0
R = fr
fr = 266.92 N
Y Axis
Fy - w-W = 0
fy = 500 + 800
fy = 1300 N
b) ask the friction coefficient
the firefighter's distance is
cos 60.08 = x₃ / 9.00
x₃ = 9 cos 60
x₃ = 5.28 m
from equation 1
R = (w x + W x₃) / y
R = 500 3.74 + 800 5.28) / 13
R = 468.769 N
we saw that
fr = R = 468.769
The expression for the friction force is
fr = μ N
in this case the normal is the ratio to pesos
N = Fy
N = 1300 N
μ N = fr
μ = fr / N
μ = 468,769 / 1300
μ = 0.36
<span>A(n) alpha particle is a particle that contains two protons, two neutrons, and has a 2 charge.
</span>
b. alpha
It occurs as detrital grains in sedimentary rocks. It forms under extreme pressure.
Water is a compound because it always has two hydrogen atoms for each oxygen atom. Water can be broken down into simpler substances. Water is a compound because pure water is composed of only H₂O molecules. Each molecule of water is a chemical combination of two hydrogen atoms and one oxygen atom. Water is a type of molecular compound.

<h3>Further explanation</h3>
- Compounds are substances composed of two or more different elements chemically combined that can be separated into simpler substances only by chemical reactions.
- Water, for example, is a compound because pure water is composed of only H₂O molecules. Each molecule of water is a chemical combination of two hydrogen atoms and one oxygen atom.
- A molecular bond or covalent bond occurs as a result of electrons can be shared between atoms. Molecular compounds have molecular (covalent) bonds.
- An ionic bond occurs as a result of electrons can be completely removed from one atom and given to another. Ionic compounds have ionic bonds.
- Examples of other molecular compounds are carbon dioxide (CO₂) and glucose (C₆H₁₂O₆). Each molecule of CO₂ is a chemical combination of two oxygen atoms and one carbon atom. Each molecule of C₆H₁₂O₆ is a chemical combination of six carbon atoms, twelve hydrogen atoms, and six oxygen atoms.
- Table salt (NaCl) is a compound because it is made from more than one kind of element (Na and Cl), but it is not a molecule because the bond that holds NaCl together is an ionic bond. An electron from the outer shell of sodium is released and taken by chlorine to reach octet conditions on both sides, that is how ionic bonds occur. Thus NaCl is an ionic compound.
- A diatomic molecule is a molecule made from two atoms of the same type. For example, oxygen gas in the atmosphere is a molecule because it contains molecular bonds. It is not a compound because it is made from atoms of only one element, i.e. oxygen. Another example is hydrogen gas, nitrogen gas, and chlorine gas.
- Elements are the simplest forms of matter and therefore cannot be broken down into simpler substances by any chemical or physical reactions. Some examples of elements include hydrogen, oxygen, carbon, sodium, iron, and sulfur. Elements can combine with other elements to synthesize compounds.
<h3>
Learn more</h3>
- Which statement best explains water’s ability to dissolve covalent compounds? brainly.com/question/8223274
- How do ionic bonds differ from covalent bonds? brainly.com/question/2092388
- Which elements can react to produce a molecular compound? brainly.com/question/867874
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