What is the net force and direction of the airplane?
The net force on the plane is 700 N.
What is force?We know that force is that which causes motion. Force is a vector quantity. This implies that the force force could have both a magnitude and a direction. The direction of force is the area where the force acts towards.
In this case, we have an airplane that is acted upon by three forces;
Wind forceAir frictionForce of the engineTaking the direction of the engine force as positive and the direction of the air friction and the wind force as negative we can now obtain the magnitude of the net force that acts on the plane as;
800 N - ( 40 N + 60 N) = 700N
Hence the net force on the plane is 700 N.
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2
A balloon with a volume of 250.0 ml at sea level has a pressure of 760.0 mm of Hg.
The balloon is released and it climbs to a level with a new pressure of 600.0 mm of Hg.
What is the new volume of the balloon? [Difficulty 1]
The final volume of the balloon will be 316.6 ml
Given,
V1= 250 ml
P1= 760 mm Hg
V2=?
P2= 600 mm Hg
From the given question, the final volume can be calculated using Boyle's law.
The link between a gas's pressure, volume, and temperature is shown by Boyle's law. It asserts that under constant temperature, a gas's pressure is inversely proportional to its volume.
Boyle's law is valid only for ideal gas.
Pressure and volume are represented by a rectangular hyperbola on the graph.
P ∝ 1/V or PV = K
∴P1 x V1 = P2 x V2
⇒ 250 x 760 = 600 x V2
⇒190000 = 600 x V2
⇒190000/ 600 = V2
⇒V2 = 316.6 ml
Hence, the new volume of the balloon will be 316.6 ml.
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If you put a strong acid in 100 ml of water and then you put the same amount of a weak acid in 100 ml of water, why would the ph be lower in the beaker with the strong acid?
The pH be lower in the beaker with the strong acid because strong acid gives more hydrogen ions.
pH (potential of hydrogen) is a numeric scale used to specify the acidity or basicity an aqueous solution.
When pH is less than seven (pH<7), solution is acidic.
Hydrochloric acid is strong acid and in water dissociates completely:
HCl(aq) → H⁺(aq) + Cl⁻(aq)
Amount of hydrogen ions are the same as amount of hydrochloric acid.
At other hand, acetic acid (CH₃COOH) is weak acid and does not dissociate completely as HCl, so concentration of hydrogen ions in a solutions are very low.
Strong acids: HNO₃(nitric acid), HCl(hydrochloric acid), H₂SO₄(sulfuric acid), HI(hydroiodic acid).
Weak acids:CH₃COOH (acetic acid), H₂CO₃ (carbonic acid), HCN (cyanic acid).
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3.35 kg N2O5
Express your answer using three significant figures.
Please help me! explain the steps for better understanding.
Answer:
31.0
Explanation:
Lets convert to grams
3.35 x 1000 = 3350 grams of N2O5
3350 / molar mass of N2O5 (108 grams) = 31.0 moles
Consider 1 l of air in a patients lungs at 37 c and 1.00 atm pressure. what volume would this air occupy if it were at 25 c under a pressure of 5.00 x 10^2 atm.
The volume of the air occupies can be 0.001922 L = 1.92mL.
To calculate the volume , the given data's are,
P₁ = 1.0 atm,
V₁ = 1 L,
T₁ = 37°C
P₂ = 500.0 atm,
T₂ = 25°C
What is the law of ideal gas?The standard definition of the ideal gas law can be stated as that for any gas, its volume (V) multiplied by its pressure (P) is equal to the number of moles of gas (n) multiplied by its temperature (T) multiplied by the ideal gas constant, R.
we can use the formula for general law of ideal gas:
PV = nRT.
where, P is the pressure of the gas in atm,
V is the volume of the gas in L,
n is the no. of moles of the gas in mol,
R is the general gas constant,
T is the temperature of the gas in K.
If n is constant, and have two different values of (P, V and T):
P₁V₁T₂ = P₂V₂T₁
P₁ = 1.0 atm, V₁ = 1 L, T₁ = 37°C + 273 = 310 K.
P₂ = 500.0 atm, V₂ = ??? L, T₂ = 25°C + 273 = 298 K.
Hence,
V₂ = P₁V₁T₂/P₂T₁
= (1.0 atm)(1 L)(298 K)/(500.0 atm)(310 L)
= 0.001922 L
= 1.92 mL.
Hence, the volume of the air occupy is 1.92 mL.
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A red glaze on porcelain can be produced by using mnso4. what is the name of the compound?
The name of the compound is manganese (II) sulfate.
In most cases, the inorganic compound with the formula [tex]MnSO_{4} . H_{2} O[/tex] is referred to as manganese(II) sulfate. A manganese(II) salt with great commercial value is this light pink deliquescent solid. For purposes that are compatible with sulfates, manganese sulfate is a relatively water- and acid-soluble manganese source.
When a metal is substituted for one or both of the hydrogen atoms in sulfuric acid, salts or esters known as sulfate compounds are created.
Blacks, browns, and purples are produced through the use of manganese as a coloring agent in bodies and glazes. Most glaze melts can easily dissolve smaller amounts of manganese; however, at concentrations above 5%, the manganese will precipitate and crystallize. Metallic surfaces are likely when a glaze contains a lot of metal (like 20%).
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Current of 4.59 a is passed through a fe(no3)2 solution for 1.80 h . how much iron is plated out of the solution?
8.6057 g iron is plated out of the solution.
The process of depositing a layer of one metal over the surface of another metal by passing electric current is called electroplating. Electroplating of metals is done to protect them from corrosion and for decoration purpose. For example, the vessels of iron are electroplated with copper or silver or gold to make it attractive and to protect from rusting.
Given,
Current = 4.59 A
Time = 1.80hr
Given solution is Fe(NO3)2
Now,
we have to find out the iron which is plated out of the solution
So,
(4.59 C/sec) (6480 sec) = 29,734.2
29,734.2 C / 96485 C/mol =0.3082 mole of electrons passed
Fe2+ + 2e- ---> Fe
0.3082 mol e- / 2 mol e- per mole Fe = 0.1541 mol Fe
(0.1541 mol) (55.845 g/mol) = 8.6057 g.
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The half-life of strontium-90 is 28 years. how long will it take a 100-mg sample to decay to a mass of 56 mg? (round your answer to the nearest whole number.)
The half-life of strontium-90 is 28 years. It will take 52 years a 100-mg sample to decay to a mass of 56 mg.
What is half life period?A half-life is just the amount of time it takes for something to go from 100% to 50%. The phrase is most frequently used in reference to radioactive decay, which happens when energetic atomic particles that are unstable lose momentum. There are 29 elements that have been shown to be susceptible to going through this process.Number of half lives that have passed is n, and the fraction that is left is equal to 0.5n.
Given that one half life is equal to 28 years, we must find n in this situation, and the remainder will be equal to 16/56, or 0.28.
0.28 = 0.52^n n = 2
after 1 half life = 0.52 remains.
after 2 half lives= 0.28 remains
Therefore, one half life is 28 years, it will take two half lives for 56 mg to decompose into 16 mg, which is equal to 52 years.
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1. Which of the following is NOT made of cells?
a. bacteria
b. leaf
C. sand
d. snail
Answer:
Sand is not made of cells
Answer:
C. sand
Explanation:
Bacteria is living so it is made of cells. A leaf is living so it is also made of cells. A snail is also a living thing, so it is made of cells. The only thing there that is not living is sand. So sand is not made of cells.
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8. For water, propane, and carbon dioxide, compare the heat of fusion to the heat of
vaporization. What patterns do you see? Do you think these patterns hold true for
other substances as well? Why is vaporization greater than fusion in every case?
The heat of vaporization is always greater than the heat of fusion because gas molecules have the largest intermolecular space and lowest intermolecular interaction.
What is latent heat?The term latent heat refers to the kind of heat that can not be detected hence the term ‘latent’. It is the heat that does not lead to temperature change. Rather the heat energy is used to break up the secondary bonds that hold the molecules and the bonds that hold the substance together in order to free the molecules of the substance.
Now if we consider water, propane, and carbon dioxide. We could see that water has the strongest intermolecular force followed by carbon dioxide and then propane. This is because water molecules are held together by hydrogen bonds while the propane molecules are only held together by the weak Van Der Walls forces.
We can now see that when we compare the heats of heat of fusion to the heat of vaporization, the heat of vaporization is always greater than the heat of fusion because gas molecules have the largest intermolecular space and lowest intermolecular interaction.
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There are three stable forms of neon: neon-20, neon-21, and neon-22. Which statement is true?
A) The number of neutrons are the same.
B) Their number of protons differ.
C) They are radioactive, like all isotopes.
D) Their atomic masses differ.
Looking at the forms of neon in the question as shown, we can see that; their atomic masses differ. Option D
What are isotopes?The term isotopes has to do with the atoms that have the same atomic number but do not have the same mass number. The mass number is the sum of the number of protons and the neutrons. Given that the number of protons is a constant and it is the identity of the element, we are now left with the understanding that the difference between the mass numbers of the isotopes must stem from the very given fact that the neutrons that are found in the both isotopes are just not of the same number.
Having said all of these, we could now look at the isotopes that we have which are the isotopes of neon that have all been labeled as; neon-20, neon-21, and neon-22.
Following from the explanations that have been afore given above, we could easily arrive at the conclusion that; their atomic masses differ.
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Ow many molecules of ethanol (c2h5oh) (the alcohol in alcoholic beverages) are present in 630 ml of ethanol? the density of ethanol is 0.789 g/cm3.
Taking into account the definition of density and Avogadro's number, 65.07×10²³ molecules of ethanol are present in 630 ml of ethanol.
We can calculate density to determine how much mass there is in a given volume of a substance. The quotient of a body's mass and the volume it occupies is therefore the formula for calculating density:
Density = mass / volume
So, 0.789 = mass / 630
mass =497.07grams
Then the number of moles that 110.46 g of ethanol contain is calculated by: 497.07/46 = 10.80 moles
The number of particles that make up a substance (often atoms or molecules) and may be found in a mole of that substance is known as Avogadro's Number or Avogadro's Constant. The number of particles per mole is [tex]6.022*10^{23}[/tex]. Any substance can be calculated using Avogadro's number.
So, amount of molecules= (10.80 moles× 6.023×10²³ molecules)÷ 1 mole = 65.07×10²³ molecules.
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A compound is analyzed and found to contain 92.24% carbon, 7.76% hydrogen. Calculate the
mass of the compound that contains 185.0 g of hydrogen.
The mass of the compound that contains 185.0 g of hydrogen is 2384.02 g
Data obtained from the questionThe following data were obtained from the question:
Percentage of carbon = 92.24%
Percentage of hydrogen = 7.76%
Mass of hydrogen = 185.0 g
Mass of compound =?
How to determine the mass of the compoundThe mass of the compound can be obtained as illustrated below:
Percentage of hydrogen = (mass of hydrogen / mass of compound) × 100
7.76% = 185 / mass of compound
0.0776 = 185 / mass of compound
Cross multiply
0.0776 × mass of compound = 185
Divide both sides by 0.0776
Mass of compound = 185 / 0.0776
Mass of compound = 2384.02 g
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Practice another a small mailbag is released from a helicopter that is descending steadily at 1.63 m/s. (a) after 5.00 s, what is the speed of the mailbag?
After 5.00 s, the speed of the mailbag is 50.63 m/s.
v = 1.63 m/s; the initial speed of a small mailbag
a = 9.8 m/s²; the acceleration of a small mailbag
t = 5.00 s; time
Ending speed is defined as the speed attained by a body after completing distance at certain time interval:
v(ending speed) = v(initial speed) + a × t
v(ending speed) = 1.63 m/s + 9.8 m/s² · 5.00 s.
v(ending speed) = 50.63 m/s
Velocity is equivalent to a specification of its speed and direction of motion, for example 100 km/h to the east.
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What is generally true about the compressibility of solids
solids are not compressible, this is why it has a fixed shape
Sarah measures out 151 grams of SO2. How many moles is this? Express your answer to three significant figures.
151 grams of SO2 is equal to
moles.
Answer:
151 g SO₂ × [1 mol SO₂/64.06 g SO₂] = 2.36 mol SO₂
Explanation:
Answer:
2.36
Explanation:
got ir right on plato
Which is a characteristic of the electron sea model for metallic bonding? molecular orbitals overlap to produce bands. electrons flow easily between metal nuclei. electrons are in fixed positions in the orbitals. atomic nuclei are arranged in an irregular pattern.
Atomic nuclei are arranged in a regular pattern is a characteristic of the electron sea model for metallic bonding.
The electron sea model is a popular model for metallic bonding. In this model, atoms are arranged in a regular pattern and each atom has a "sea" of electrons around it. This sea of electrons is responsible for the metallic bond.
The main advantage of the electron sea model is that it can explain the properties of metals very well. For example, why metals are good conductors of electricity and heat.
One of the drawbacks of the electron sea model is that it doesn't explain why some metals are magnetic. This is because the model assumes that all of the electrons are in the same orbital and spin in the same direction. However, we know that some electrons do spin in the opposite direction, which creates a magnetic field.
Overall, the electron sea model is a good way to understand the basics of metallic bonding. However, it doesn't explain everything and there are some limitations to the model.
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Answer:
Electrons flow easily between metal nuclei
Explanation:
The density of acetone is 0.702 g/ml. how much in grams does 9.85 x 10 -2 l mass? (report answer in 4 sf).
Mass of acetone is 69.147 grams.
V(acetone - C₃H₆O) = 9.85 × 10⁻² l
V(acetone) = 0.0985 l
V(acetone) = 98.5 ml; volume of acetone
d(acetone) = 0.702 g/mL; density of acetone
m(acetone) = V(acetone) × d(acetone).
m(acetone) = 98.5 ml × 0.702 g/ml.
m(acetone) = 69.147 g; mass of acetone
Acetone or propanone is the colorless, volatile, flammable organic compound (ketone).
Density is the mass of an object divided by its volume. The SI derived unit for density is the kilogram/cubic meter, but chemist usually use gram per milimeter.
Mass is a fundamental measure of the amount of matter in the object.
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Which amino acid residue's backbone forms a hydrogen bond with the backbone of the third (3rd) residue?
Amino acid 7 residue's backbone forms a hydrogen bond with the backbone of the third (3rd) residue.
What are amino acids?
An amino acid is an organic molecule composed of a basic amino group (NH 2), an acidic carboxyl group (COOH), and an organic R group (or side chain) that is unique to each amino acid. Informally, an amino acid is alpha-amino [alpha-amino] carboxylic acid.
The hydrogen atoms on both of the leftover groups must be bound to electronegative atoms for hydrogen bonding to take place between the residual molecules of the second molecule. Fluorine, oxygen, nitrogen, and chlorine are some of these atoms. These atoms have the capacity to impart a charge on the hydrogen atom, enabling hydrogen bonding.
Amino acid 7 residue's backbone forms a hydrogen bond with the backbone of the third (3rd) residue.
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Please help
1. What do you know already about the reactions of metals with water, acids and with the air (oxygen)?
2.Is it unusual for a metal to react with cold water (H20) ?
3.Is it usual for a metal to react with dilute hydrochloric acid? If it is, what are the products of the reaction (think coursework ...
magnesium and hydrochloric acid)
4. Is it usual for a metal to react with air / oxygen? If it is, what type of product forms?
Answer:
1: A salt plus hydrogen gas
2: Yes, the metals which react with cold water are; sodium, calcium and potassium. Magnesium does not react with cold water. Metals like aluminum, iron and zinc do not react either with cold or hot water. Metals such as lead, copper, silver and gold do not react with water at all.
3: There is no reaction between dilute hydrochloric acid or sulfuric acid and the metals below hydrogen in the reactivity series.
4: Yes. The product that forms is called rust.
What is the ph at the equivalence point in the titration of 100 ml of 0.10 m hcn with 0.10 m naoh?
The ph at the equivalence point in the titration of 100 ml of 0.10 m HCN with 0.10 m NaOH is 11.04.
To ascertain the concentration of an identified analyte, titration is a typical laboratory technique for quantitative chemical analysis. A standard solution with a known concentration and volume is prepared as the reagent, also known as the titrant or titrator.
The food business uses titration extensively as an analytical method. It enables food producers to estimate the concentration of a reactant in a sample. For instance, it can be used to determine a food's salt or sugar content or the amount of vitamin C or E, which affects the color of the product.
[tex]HCN + OH^{-}[/tex] →[tex]H_{2}O + CN^{-}[/tex]
At the equivalence point, 10 mmol of cyanide ions are held in 200 mL of solution.
[[tex]CN^{-}[/tex]] = 10 mmol/200 mL = 0,05 M
Kb = [tex]\frac{ 1.0E^{-14} }{4.9E^{-10} }[/tex]
Kb = 2.0E-5 corresponding to [tex]CN^{-}[/tex] + [tex]H_{2}O[/tex]= HCN + [tex]OH^{-}[/tex]
Kb =[tex]\frac{[HCN][OH^{-}}{CN^{-}}[/tex]
y=0.0011 M =[[tex]OH^{-}[/tex]]
pOH = 2.96
pH = 14.00 - pOH = 11.04
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Define Projectile:
A projectile is launched with an initial horizontal velocity from a cliff and follows a parabolic path to the ground. Predictable unknowns include the initial speed of the projectile, the initial height of the projectile, the time of flight, and the horizontal distance of the projectile.
A projectile is launched with an initial horizontal velocity from a cliff and follows a parabolic path to the ground and include the initial height of the projectile
Projectile is a body projected by external force and continuing in motion by its own inertia and the velocity is constant horizontally it means that means the acceleration is zero and initial vertical velocity is zero projectiles travel with a parabolic path due to the fact that the downward force of gravity accelerates them downward from their straight-line gravity-free
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What can you determine from the following scenario?
An object at rest is pulled in opposite directions by unequal forces.
Use claims, evidence, and reasoning
The object at rest moves to the direction of the greater force when it is pulled in opposite directions by unequal forces.
According to Newton’s first law of motion, a body at rest does not move until an external force is applied to it.
When an equal force is applied in the opposite directions, the object remains at rest as the net force becomes zero.
When an unequal force is applied in the same direction, the body moves in the direction of the force being applied, but when the unequal forces are in opposite direction, the object moves in the direction which has greater force.
The net force, which results from the difference between two unequal forces acting in opposition on an object, is what moves it. Resultant is the name given to the overall or net force and its direction.
For example, a force of 30N is applied from the right and 55N is applied from the left on an object. The net force will be 55 – 30 = 25N. Therefore, the object will move to the left with a force of 25N.
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Uring oxidative phorphorylation, atp is produced as hydrogen ions move from across the innermembrane from the ________ to ___________
During oxidative phosphorylation, ATP is produced as hydrogen ions move from across the innermembrane from the matrix to intermembrane space.
Oxidative phosphorylation is the process in which adenosine triphosphate (ATP) is synthesed.
It is generating 36 ATP molecules per one molecule of glucose.
This process consume oxygen and it is coupled to the movement of electrons through the mitochondrial electron transport chain.
Movement of hydrogen ions makes proton concentration gradient between the intermembrane space and the matrix, which is used for production of ATP (see the picture below).
There are four protein complexes in the innermembrane involved in transport of protons and electrons.
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What volume in ml of 0.05 m h2so4 can be prepared from 2.5 g h2so4 and sufficient water?
12.5 volume in ml of 0.05 m Sulphuric can be prepared from 2.5 g sulphuric acid and sufficient water.
What is Volume?
Volume is a measurement of three-dimensional space that is occupied. It is frequently expressed numerically using imperial or SI-derived units. Volume and the notion of length are connected.
As a result, we can observe that 0.5 moles of sulphuric acid are required to neutralise 1 mole of NaOH. Now let's figure out how much NaOH is specified.
NaOH is assumed to weigh 2.5 g.
NaOH has a molar mass of 40 g.
=> 62.5 millimoles of NaOH are equal to 2.540 moles.
The required amount of sulfuric acid is 62.5/2 millimoles, or 31.25 millimoles.
We now understand that millimoles equal molarity times volume (in ml)
replacing the specified values,
31.25 = 2.5 * V
=> V = 12.5 ml
As a result, 12.5 cc of sulfuric acid is needed.
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Just question 2 pleasee
The correct matching of the properties of the elements are;
Rubidium - catches fire as soon as it s exposed to air and burns fiercely
Lithium - hard to set alight but burns with a deep red flame
Potassium - Melts readily on heating with a Bunsen flame and catches fire easily. Burns with a mauve flame.
Sodium - Melts fairly readily with Bunsen flame then catches fire and burns with a deep yellow flame
What are the properties of the elements?We know that elements are classified into groups. The groups are a family of elements that have similar chemical and physical properties. Now we have the to match the properties of the elements as shown;
Rubidium - catches fire as soon as it s exposed to air and burns fiercely
Lithium - hard to set alight but burns with a deep red flame
Potassium - Melts readily on heating with a Bunsen flame and catches fire easily. Burns with a mauve flame.
Sodium - Melts fairly readily with Bunsen flame then catches fire and burns with a deep yellow flame
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What is the ph of a buffer solution prepared with 0.055 m sodium acetate and 0.01m acetic acid. the pka value of acetic acid is 4.76 at 250c.
The ph of a buffer solution prepared with 0.055 m sodium acetate and 0.01m acetic acid at the pka value of acetic acid is 4.76 at 250c is 5.5.
What is a buffer solution?A weak acid and its conjugate base, or vice versa, are combined to form an aqueous solution known as a buffer solution (more specifically, pH buffer or hydrogen ion buffer). A little bit of a strong acid or base applied to it barely affects its pH.
Strong acids or bases applied in modest amounts don't cause buffer solutions to shift pH. An illustration of a buffer made up of a weak acid and its salt is a solution of acetic acid and sodium acetate CH3COOH + CH3COONa.
The three primary buffer systems in the human body are the phosphate, protein, and carbonic acid bicarbonate systems.
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Attractions between the negative oxygen atom of one water molecule and the positive hydrogen atom of another water molecule are called.
Attractions between the negative oxygen atom of one water molecule and the positive hydrogen atom of another water molecule is called hydrogen bond.
Water molecule is made up of one oxygen atom and one hydrogen atom. Each hydrogen atom shares an electron pair with the oxygen atom. The water molecule also contains two unshared lone pairs of electrons.
The lone pair of electrons repel each other and also repel the hydrogen atoms. This gives the water molecule a bent shape, with a hydrogen atom at each of the two corners and the unshared pairs of electrons at the other two corners. The angle between the hydrogen atoms is 104.5 degrees.
This unequal sharing of electron causes the oxygen atom to have a partial negative charge and the hydrogen atom to have a partial positive charge, causing electrostatic attractions between the hydrogen atom of one water molecule and the oxygen atom of another hydrogen atom. This attraction is called hydrogen bond.
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What is created by the flow of electric current?
Answer:
Electric current generates an accompanying magnetic field, as in electromagnets. When an electric current flows in an external magnetic field, it experiences a magnetic force, as in electric motors. The heat loss, or energy dissipated, by electric current in a conductor is proportional to the square of the current.
Explanation:
When water dissolves a substance, weak charges on water molecules attract oppositely charged portions of the substance, pulling them out into solution. Which property of water accounts for this occurrence?.