PLEASE HELP!!
A model stands on a scale and finds her weight to be 105 pounds. If
the pressure exerted by her feet on the scale is 2.16 pounds per
square inch, what is the area of her feet in cubic centimeters?
__cm2
Answer:
313.5cm²
Explanation:
Given parameters:
Weight of model = 105pounds
Pressure applied on the scale by model = 2.16pounds per square inch
Unknown:
Area of her feet in cm² = ?
Solution:
Pressure is the force per unit area;
Pressure = [tex]\frac{Force}{Area}[/tex]
Input the parameters and solve;
2.16 = [tex]\frac{105}{Area}[/tex]
105 = 2.16 x Area
Area = [tex]\frac{105}{2.16}[/tex] = 48.6in²
We need now to convert the in² to cm²
1in² = 6.45cm²
48.6in² = 48.6 x 6.45 = 313.5cm²
Which of the following is an irreversible physical change?
a) melting a piece of lead
b) sharpening a pencil
c) dissolving sugar into water
d) boiling water
Answer:
b) sharpening a pencil
Explanation:
If you melt lead, boil water, or dissolve sugar in water, you can return all of them back to their original state. If you sharpen a pencil, you can't reattach the shavings as they were originally.
You may put all of them back to their original states by melting lead, heating water to a boil, or dissolving sugar in water. You cannot rejoin the shavings from a sharpened pencil in their original position. Thus, option B is correct.
What is irreversible physical change?When something changes physically but not chemically, it has undergone an irreversible physical alteration that cannot be reversed.
Sharpening a pencil is a perfect example of an irreversible physical change. The wood turns to dust when you sharpen it. Just in a different shape, it is still wood. That wood dust cannot be transformed back into a pencil.
You cannot put a piece of paper back together the same way it was before you tore it if you tear it into tiny pieces.
An irreversible alteration is one that cannot be undone or that cannot be returned to its original state, such as when milk turns into curd, iron turns rusty, paper burns, food is cooked, etc.
Therefore, sharpening a pencil is an irreversible physical change
Learn more about irreversible here:
https://brainly.com/question/24111037
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What is the density of an object that has a mass of 62.4 grams and a volume of 7.6 cm 3 ?
(b) Define, in terms of oxidation state, the Oxidizing agent
a substance which gains oxygen
a substance whis lose hydrogen
a substance which experiences a decrease in oxidation state
a substance which experiences an increase in oxidation state
Answer: a substance whis lose hydrogen
Explanation:
Explain why warm air temperature has lower air pressure than cold air?
Answer:
Differences in temperature cause differences in air density. Warmer air is less dense than cold, which is why warm air tends to rise and cold air sinks.
temparature affects particles. warm particles are more spread out.
Explanation:
. Being acted on by gravity, colder, denser air weighs more and exerts greater pressure per unit area.
Sugar is added to iced tea and the contents are stirred until all of the sugar dissolves. How would the tea now be classified?
Which of the following is most likely NOT a chemical reaction?
(A)
A white powder and a clear liquid mix and the beaker holding the mixture gets cool to the touch
(B)
A white solid and a clear liquid mix and produce a bright orange, bubbling substance
(C)
A pan containing a clear liquid is place on a hot stove and begins to bubble after a few minutes.
(D)
A blue liquid and a green solid mix and produce a purple paste
Answer:
B is the correct answer because bubbling is a sign of chemical reaction and production of a new substance
PE = mgh, solve for m
Answer:
P.E. = mgh, where m is the mass in kilograms,
Answer:
[tex]m = \frac{PE}{gh} [/tex]
Explanation:
[tex]if \: PE = mgh \\ then \to \\ m = \frac{PE}{gh} [/tex]
♨Rage♨
What is the rule of zero charge?
Answer:
The nonmetal atoms accept electrons and form ions with a negative charge, called anions. When an ionic compound forms, the total charge on the atoms adds up to zero. This is known as the rule of zero charge.
Explanation:
The momentum of a 23 000 kg truck traveling eastward with a velocity of 50.0 m/s is kom/s
Answer:
Explanation:
I'm not sure what you mean by the units. The answer using kg and ms is 23000 * 50 = 1150000 kg m/s
Select the correct answer
Which statement best supports the idea that water conservation is important for human societies?
OA Once humans use water, it cannot be reused ever again,
OB. Only about 1% of the freshwater on Earth is easily accessible.
OC Water is constantly being lost from the hydrosphere
OD. Most land animals use salt water instead of freshwater.
Answer:
Only about 1% of the freshwater on Earth is easily accessible.
Explanation:
Freshwater accounts for a minimal proportion of water resources on planet earth. About 70 percent of the world surface area is covered by water, but only about 2.5 percent of this mass of water is fresh. The remaining are marine or salt water. Amazingly, just about 1 percent of this freshwater is easily accessible. The other 1.5% is trapped in glaciers and snowfields.
This underscore the need for water conservation on the planet since fresh water is a scarce resource and people living in many areas have no access to fresh water.
The millions of fossils that scientists have collected are called the fossil __.
Answer:
record
Explanation:
Define a force.......
Answer:
Gravitational Force.
Gravitation is the agent that gives weight to objects with mass and causes them to fall on the ground when dropped.
Answer:
A force is the strength or energy as an attribute of physical action or movement.
Explanation:
In smaller words, a force is a form of energy caused from a push or a pull on an object. A force happens when two objects interact with each other. For example, when you throw a ball you are using force.
Hopefully this helps im sorry if i got it wrong im kinda dumb... XD
IUPAC name for C3H7
Answer:
propyl
Explanation:
......:)
..;) .........
Which of the following has a higher electronegativity oxygen or selenium?
Answer: Oxygen
Explanation: Oxygen has more ionisation energy and Oxygen has a small size which makes it more electronegative.
Atomic number is equal to the number of electrons in an atom?.
Answer:
true I think not sure
Explanation:
Sodium, an alkali metal, and chlorine, a halogen, are both in Period 3 of the periodic table. Which element has
a higher ionization energy? Explain your answer.
Answer:
Chlorine has higher ionization energy.
Explanation:
Sodium is present on left side of periodic table in period 3 while chlorine is present on right side of periodic table in period 3.
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required. Thus chlorine have higher ionization energy as compared to the sodium.
Select the correct answer.
In which situation is no work considered to be done by a force?
A.
when the angle between the force and displacement is 180°
B.
when the angle between the force and displacement is 90°
C.
when the angle between the force and displacement is 45°
D.
when the angle between the force and displacement is 0°
Answer:
Explanation:
when the angle between the force and displacement is 0
How many electrons does each lithium atom provide to the voltaic cell?
A. 1
B. 2
C. 3
D. 4
Answer:
c. 3 electrons
Explanation: for the element of LITHIUM, you already know that the atomic number tells you the number of electrons. That means there are 3 electrons in a lithium atom.
In a longitudinal wave, particle displacement is
from google, so I think the answer to that question is the second one
What advances in technology helped usher in the scientific revolution? Choose the best answer.
1.The landing on the Moon by Apollo brought about the scientific revolution.
2.Discoveries by scholars in the Catholic Church revolutionized scientific knowledge.
3.The discoveries by ancient Greek, Muslim and Chinese scientists.
4.The discovery of optics gave scientists instruments such as microscopes and telescopes.
Answer:
The discovery of optics gave scientists instruments such as microscopes and telescopes.
Explanation:
The period between the 16th-8th century was called the period of the scientific revolution. At this time, the foundations of our modern science was laid.
One of the characteristic of this period was the emphasis on the scientific method which upheld results from reproducible experiments.
Nicolaus Copernicus, Francis Bacon and Isaac Newton were leading names in this period.
It was within this period that the discovery of optics gave scientists instruments such as microscopes and telescopes and scientific examination of the celestial bodies was launched.
Define the concept of Energy in your own words
Answer:
In general, the word energy refers to a concept that can be paraphrased as "the potential for causing changes", and therefore one can say that energy is the cause of any change. The most common definition of energy is the work that a certain force (gravitational, electromagnetic, etc) can do. Due to a variety of forces, energy has many different forms (gravitational, electric, heat, etc.) that can be grouped into two major categories: kinetic energy and potential energy. According to this definition, energy has the same units as work; a force applied through a distance. The SI unit of energy, the joule, equals one newton applied through one meter, for example. Energy has no direction in space, and is therefore considered a scalar quantity. Energy is a conserved quantity, meaning that it cannot be created or destroyed, but only converted from one form into another. Thus, the total energy of the universe always remains constant. One form of energy can be readily transformed into another; for instance, a battery converts chemical energy into electrical energy.
Explanation:
mL? PLEASEEE HELP
What is the answer
What is involved in weathering?
Answer:
the answer is water.Hope this helps
which element would have properties most like arsenic (As)? Te Ge P Se
Answer:
P
Explanation:
Sodium + oxygen
What colour is the flame produces
Answer:
Orange
Explanation:
I used google my b
Answer:
ORANGE
explanation:
Small pieces of sodium burn in air with often little more than an orange glow. Using larger amounts of sodium or burning it in oxygen gives a strong orange flame.
HELPPP PLEASEEE!!! calculate the energy of radiation with a wavelength of 432 nm
Which describes the motion of the car as shown by the graph?
A) travels at a constant speed
B) not moving
C) changing directions
D) speeding up
Record the length of the object shown.
Answer: 7.26 mm
I did the test already.
Burning is a type of_________reaction.
O replacement
O decomposition
O synthesis
O combustion
Answer:
Combustion
Explanation:
Happy Halloween!