You place a book on your desk, and then you begin to lift one edge of the desk. You make the following observations: At first the book does not move. When you lift the desk edge higher, the book begins to slide slowly. As you lower the desk slightly, the book slows down, then stops. Use your knowledge of forces and friction to explain your observations.

Answers

Answer 1

Explanation:

The movement of an object involves two forces: the force applied to the body which causes acceleration of the object called kinetic force and the force that opposes it called the friction. These forces are involved in the movement of the book as:

1. When a book is kept on the desk, since no external force is applied to the book therefore the book remains at rest.

2. When the desk is placed in an inclined position, the inclined position causes the sliding of the book but as the book moves down the force of friction increases which causes the book to come at rest. This force of friction is known as the sliding force.

Answer 2

The movement of the book on the table has been attributed to the applied force in the inclined position, while the slowing down of the book's motion contributes to the friction.

What is force and friction?

Force can be defined as the pressure exerted to produce the motion of the object. The friction has been the stopping force that stops the motion of the object.

The inclination of the table resulted in the application of tangential force to the book, that favors the motion of the object.

The lowering of the table results in the stopping of the motion of the book. The lesser stopping force of the book motion was favored with the frictional force between the book and the table.

Learn more about force, here:

https://brainly.com/question/26115859


Related Questions

If 119.5 g of iron is mixed with 279.50 g of copper (II) nitrate, what is the limiting reagent for the reaction?

Answers

Answer:

Copper ii nitrate is the limiting reagent

Explanation:

The first thing to write here is the equation of reaction;

Fe + Cu(NO3)2 ——> Fe(NO3)2 + Cu

When we talk of limiting reagent, we mean the reactant that is totally consumed upon the completion of the chemical reaction

To get the limiting reagent, we can know this by calculating the mass of a specific product formed from each of the masses of the reactants

Now, we can use the amount of copper solid deposited by each of the reactants to know the limiting reagent here.

Since the mole ratio in all cases is 1 to 1, this will be easy

For the iron, the number of moles reacted is mass of iron/ atomic mass of iron

That would be 119.5/56 = 2.134 moles

Now since the mole ratio is 1 to 1, 2.134 moles of copper will be formed

Thus, the mass of copper produced from the iron will be number of moles * atomic mass of copper = 2.134 * 64 = 136.57g

Now from the nitrate, the number of moles is

mass mixed/ molar mass of copper nitrate

molar mass of copper nitrate is 188g/mol

number of moles is thus 279.5/188 = 1.487 moles

Since the mole ratio is 1 to 1, it means that the number of moles of copper produced too is 1.487 moles

The mass of copper produced from this is number of moles of copper * atomic mass of copper

That will be 1.487 * 64 = 95.15g

Now, since the copper nitrate produces less amount of copper solid, it is the the reagent to be consumed first and thus it is our limiting reagent

What is the mass by precent of oxygen in carbon dioxide (co2)

Answers

Answer:

Oxygen has a molar mass of 16.0 g mol−1 , so 1 mole of oxygen atoms has a mass of 16.0 g . Therefore, carbon dioxide has a percent composition of 72.7% oxygen, i.e. for every 100 g of carbon dioxide you get 72.7 g of oxygen

Explanation:

Another chemistry question. Help me!
To prepare 250cm³ of standard solution of 1.0 mol dm-³ sodim carbonate Na2Co3​

Answers

Answer:

Molar mass Na2CO3 = 2*23 + 12 + 3*16 = 106 g/ mol

Mass of 1 mol Na2CO3 = 106 g

mass (Na2CO3) = 106g*250cm³/1000cm³ = 26.5 g

1) It is necessary because all Na2CO3 will be in the solution, and no Na2CO3 would be lost.

2) Because the solution that was formed after rinsing beaker contains Na2CO3.

3) Eyes should be on the level of calibration mark of the volumetric flask.

4) It is necessary to prevent evaporation of water, and changing , because of it, the concentration of the solution.

5. What volume would you need to dilute 0.2 L of a 15 M solution to obtain a 3 M
solution?

Answers

Answer:

IL

Explanation:

M_1 V_1 = M_2 V_2

M_1 = 15 M

V_1 = 0.2 L

M_2 = 3 M

V_2 = ?

15 x 0.2 = 3V_2

15 x 0.2 = 3

3 / 3V_2

1 L= V_2

1 L is the volume that would be needed to dilute 0.2 L of a 15 M solution to obtain a 3 M solution.

What is volume?

A measurement of three-dimensional space is volume. It is frequently expressed quantitatively in SI-derived units, other imperial units, or US customary units. Volume and the notion of length are connected. In contrast to how much space the container actually occupies, the overall size of a container is typically thought of as its capacity, or the quantity of fluid it could hold.

Volume was initially measured using naturally occurring vessels of a comparable shape and then with standardised containers. Arithmetic formulas can be used to quickly calculate the volume of several straightforward three-dimensional shapes.

Molarity₁×Volume₁=Molarity₂×Volume₂

15 x 0.2 = 3×Volume₂

15 x 0.2 = 3

3 / 3=Volume₂

1 L=Volume₂

Therefore, 1 L is the volume that would be needed to dilute 0.2 L of a 15 M solution to obtain a 3 M solution.

To know more about volume, here:

https://brainly.com/question/23477586

#SPJ2

Can Chlorine be harmful to any of the earth’s ecosystems? If so how?

Answers

Answer:

Although chlorine itself usually does not cause environmental harm, it combines rapidly to form chemicals such as dioxins that pollute water, contaminate fish and transfer to humans and larger animals that eat the fish.

Explanation:

What does "A" represent in a the standard form of a double replacement reaction? a.) otion b.) cation

Answers

Answer: cation

Explanation:

"A" represent in a cation in the standard form of a double replacement reaction. Therefore, option B is correct.

What is cation ?

Positively charged ions are known as cations. Negatively charged ions are known as anions. Ions are positively or negatively charged atoms or molecules. A balanced atom will become a positively charged cation if one or more electrons are lost.

In an electrical field, these ions are known as "cations" because they are positively charged and migrate toward the negative electrode (cathode).

The double-replacement reaction generally take up the form of AB + CD → AD + CB where A and C are positively-charged cations and B and D are negatively-charged anions.

Thus, option B is correct.

To learn more about the cation, follow the link;

https://brainly.com/question/28710898

#SPJ6

Name two drying agents that can be use to dry hydrogen gas​

Answers

CaCl2, Na2SO4, MgSO4 are three drying agents that can be used to dry hydrogen gas

84. A salution of a substance x is used
of a
for
il Name the sulsstance 'x' and the
white kashing
write its farmula
il y Write the reaction the substance
la' named in il above with water.
of
dne

Answers

Answer:

Following are the answer to this question:

Explanation:

(1) Calcium oxide (CaO) is also referred to as quicklime. It is the solution for the substance used for whitewashing.  

Whenever it reacts with water ([tex]H_2O[/tex]) and absorbs carbon dioxide ([tex]CO_2[/tex]), it then formed calcium carbonate ([tex]CaCO_3[/tex]), which produced a hard laminate on the walls, to first be whitened by the production of calcium hydroxide (CaOH).  

(2) Slackened lime or calcium hydroxide arises whenever the fast limestone reacts with water.

[tex]CaO(s) + H_2O(l) \rightarrow Ca(OH)_2(aq).[/tex]

PLEASE HURRRYYYY

A buffer is made using HCO2Na. Which other substance should the buffer contain?

HCO2Li

HCO2H

NaNO3

HCl

Answers

Answer:

HCO₂H

Explanation:

A buffer is defined as the mixture between a weak acid and its conjugate base, or vice versa, in an aqueous solution.

The HCO₂Na (Sodium formate), is the conjugate base of formic acid, HCO₂H, a weak acid of pKa = 3.75.

Thus, to make a buffer using HCO₂Na, the other substance the buffer should contain is HCO₂H

Answer:

HCO₂H

Explanation:

Jaiden is writing a report about the structure of the atom. In her report, she says that the atom has three main parts and two subatomic particles. Do you agree with her? Why or why not?

Answers

Answer:

The smallest constituent of an element is termed as an atom. According to Jaiden, an atom comprises two subatomic particles and three prime parts, however, this is incorrect as an atom comprises three subatomic particles and two main parts. The three subatomic particles are the protons, electrons, and neutrons. All these parts are smaller in comparison to an atom, thus, they are considered as subatomic particles.  

To be considered as an atom, an atom is needed only electrons and neutrons, like hydrogen exhibit one electron and one proton. On the other hand, the overall charge of the atom is not affected by the presence of neutrons, it is the subatomic particle that only enhances the mass of the atom.  

Answer:

I disagree with her because an atom has two main parts: the nucleus and the electron cloud. Atoms have three subatomic particles: protons, neutrons, and electrons.

Explanation:

The minerals of aluminium include all of the following except
A. corundum
B. kaolin
C. Bauxite
D. Cryolite​

Answers

Bauxite I think , it’s probably C
It is cryolite because all the other 3 are forms of aluminum while cryolite is used to extract it

if the balloon is 67,000 L at STP, what volume would it be if the air temperature cool to10.0°C in the pressure dropped to 99.2kPa as the balloon went higher?

Answers

Answer: The volume is 70872 L

Explanation:

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

The combined gas equation is,

[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]

where,

[tex]P_1[/tex] = initial pressure of gas (STP) = 1 atm

[tex]P_2[/tex] = final pressure of gas = 99.2 kPa = 0.98 atm  (1kPa=0.0098atm)

[tex]V_1[/tex] = initial volume of gas  = 67000 L

[tex]V_2[/tex] = final volume of gas = ?

[tex]T_1[/tex] = initial temperature of gas (STP)  = 273K

[tex]T_2[/tex] = final temperature of gas = [tex]10.0^0C=(273+10)K=283K[/tex]

Now put all the given values in the above equation, we get:

[tex]\frac{1\times 67000}{273}=\frac{0.98\times V_2}{283}[/tex]

[tex]V_2=70872L[/tex]

Thus the volume is 70872 L

Calculate the molar mass of CH4 gas at STP when 5.46Lof the gas weighs 4g??​

Answers

Answer:

About 16.42 grams

Explanation:

[tex]PV=nRT \\\\(1)(5.46L)=n(0.0821)(273) \\\\n\approx 0.2436 \\\\4g/0.2436\approx 16.42[/tex]

Hope this helps!

PLS HELP ! 5.00 mL of a stock solution, containing 0.200 M of Na3PO4 was pipetted into a 25.00 mL volumetric flask and made up to the calibration mark with deionised water. A serial dilution was carried out for another two times to obtain the final solution of desired concentration. Calculate the concentration of the final solution, express in ppm (by volume).

Answers

Answer:

262 ppm of Na₃PO₄

Explanation:

In a dilution, the concentration of the initial solution is decreased. When you take 5.00mL of the solution that is diluted to 25.0mL The solution is diluted 25/5 = 5 times

If you make another two serial dilutions the final solution wil decrease its concentration 5*5*5 = 125 times

As original solution containing 0.200 M of Na3PO4, the final solution will have a concentration of:

0.200M / 125 = 1.6x10⁻³M

Molarity is defined as the ratio between moles and liters. 1.6x10⁻³ moles of Na3PO4 in 1L are:

1.6x10⁻³mol ₓ (164g/mol) = 0.262g Na₃PO₄ / L

Assuming density of Na3PO4 as 1g/mL the concentration of the solution is:

0.262mL Na₃PO₄ / L

As 1mL = 1000μL:

262μL Na₃PO₄ / L

μL of solute per L of solution is equal to ppm, that means the solution has:

262 ppm of Na₃PO₄

Keeping in mind the rules for significant dig-
its, what is the product of 0.6906 m and 4.03
m?

Answers

Answer:

2.78

Explanation:

When multiplying, your answer will have the same amount of sig figs as the multicand or multiplier that has the lower number of sig figs. In this case, 4.03 is the one with the lowest number of sigs figs, which is 3 sig figs, so the answer should have 3 sig figs, so the answer is 2.78.

2 Points
A student blows a whistle. In which direction do the air particles vibrate with
respect to the direction the sound wave travels?

A. Perpendicular to

B. Parallel to

C. At a 45 degree angel to

D. At an unpredictable angel

Answers

Answer:

parallel to

Explanation:

In parallel direction the air particles vibrate with respect to the direction the sound wave travels. The correct option is B.

What is sound wave?

A sound wave is the pattern of disturbance caused by the movement of energy as it propagates away from the source of the sound through a medium (such as air, water, or any other liquid or solid matter).

Sound waves are produced by object vibrations and pressure waves, such as a ringing cellphone.

Because sound waves are produced by compressions and rarefactions in the air, they are referred to as longitudinal waves. The air particles vibrate in a direction parallel to the propagation direction.

The particles in a longitudinal wave are displaced parallel to the direction of the wave. Compressions moving along a slinky are an example of longitudinal waves.

Air particles vibrate in a parallel direction to the direction of travel of the sound wave.

Thus, the correct option is B.

For more details regarding sound waves, visit:

https://brainly.com/question/21995826

#SPJ2

Explain Redox tiltration and examples of half - life reactions.​

Answers

Answer:

Explanation:

Half life reactions take place in electrochemistry where u have to find the emf generated from a cell

E.g Mg(s)/Mg(aq)//Ag(aq)/Ag(s)

so ...this is the question and I hope you get it right one​

Answers

Answer:

About 96 grams per mole

Explanation:

The chemical formula of ammonium carbonate is [tex](NH_4)_2CO_3[/tex]. This means that breakdown of moles of atom per mole of molecule is:

2 moles of nitrogen, with a molar mass of around 14

8 moles of hydrogen, with a molar mass of around 1

1 mole of carbon, with a molar mass of about 12

3 moles of oxygen, with a molar mass of about 16

The molar mass of ammonium carbonate is therefore:

2(14)+8(1)+1(12)+3(16)=28+8+12+48=about 96

Hope this helps!

Which of the following best describes why a cruise ship floats?
A. It displaces an equal or greater amount of water than its own
weight.
B. It displaces more than half of its weight in water.
C. Its volume and mass are equal.
D. Its volume is greater than its mass.

Answers

Answer:

A. It displaces an equal or greater amount of water than its own weight.

Explanation:

How many grams of H2S is needed to produce 18.00g of PbS if the H2S is reacted with an
excess (unlimited) supply of Pb(CH3COO)2?

Answers

Answer:

2.56 grams of H₂S is needed to produce 18.00g of PbS if the H2S is reacted with an  excess (unlimited) supply of Pb(CH₃COO)₂

Explanation:

The balanced reaction is:

Pb(CH₃COO)₂ + H₂S → 2 CH₃COOH + PbS

By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction) they react and produce:

Pb(CH₃COO)₂: 1 moleH₂S: 1 moleCH₃COOH: 2 molesPbS: 1 mole

In this case,  to know how many grams of H₂S are needed to produce 18.00 g of PbS, it is first necessary to know the molar mass of the compounds H₂S and PbS and then to know how much it reacts by stoichiometry. Being:

H: 1 g/moleS: 32 g/molePb: 207 g/mole

The molar mass of the compounds are:

H₂S: 2* 1 g/mole + 32 g/mole= 34 g/molePbS: 207 g/mole + 32 g/mole= 239 g/mole

So, by stoichiometry they react and are produced:

H₂S: 1 mole* 34 g/mole= 34 gPbS: 1 mole* 239 g/mole=   239 g

Then the following rule of three can be applied: if 239 grams of PbS are produced by stoichiometry from 34 grams of H₂S, 18 grams of PbS from how much mass of H₂S is produced?

[tex]mass of H_{2} S=\frac{18 grams of PbS*34 grams of H_{2}S }{239 grams of PbS}[/tex]

mass of H₂S= 2.56 grams

2.56 grams of H₂S is needed to produce 18.00g of PbS if the H2S is reacted with an  excess (unlimited) supply of Pb(CH₃COO)₂

can periodic table indicates occurrance of the elements, why?​

Answers

Answer: No

Explanation:

A periodic table can be defined as the table in which the row of chemical elements are present. All the elements of the row have same number of electron shells.

The arrangement of elements is based on atomic numbers, electron shell model and other chemical properties. The elements are placed in increasing order of atomic number.

This table does not give information about the occurrence of the elements.

Which of these observations are not explained by kinetic-molecular theory?

Answers

The question's incomplete unfortunately, which observations?

Answer:

At very low temperatures, gases expand less for a given pressure change than they do at high temperatures

Which symbol can be used to indicate the pressure at which a chemical reaction is carried out?
25°C
2 atm
Pt

Answers

Answer:

2atm symbol can be used to indicate the pressure at which a chemical reaction is carried out

Which element is needed for
a. Bone and teeth formation.
b. Treatment of water.

Answers

Bone and teeth formation
Treatment of water

Answer:

a.calcium

b.chlorine

whats the chemical formula for dilute hydroxide acid​

Answers

the chemical formula is OH −

Another name for a statovolcano is a _____ volcano because it is made of alternating layers of thick, sticky lava and volcanic rock and ash. A. shield B. cinder C. composite D. pyroclastic

Answers

Answer:

Bcinder

Explanation:

Cu+2AgNO

3



→2Ag+Cu(NO

3



)

2



start text, C, u, end text, plus, 2, start text, A, g, N, O, end text, start subscript, 3, end subscript, right arrow, 2, start text, A, g, end text, plus, start text, C, u, left parenthesis, N, O, end text, start subscript, 3, end subscript, start text, right parenthesis, end text, start subscript, 2, end subscript

How many grams of \text{Ag}Agstart text, A, g, end text will be produced from 19.0 \text{ g}19.0 g19, point, 0, start text, space, g, end text of \text{Cu}Custart text, C, u, end text and 125 \text{ g}125 g125, start text, space, g, end text of \text{AgNO}_3AgNO

3



start text, A, g, N, O, end text, start subscript, 3, end subscript?

Answers

Answer:

Mass of Ag produced = 64.6 g

Note: the question is, how many grams of Ag is produced from 19.0 g of Cu and 125 g of AgNO3

Explanation:

Equation of the reaction:

Cu + 2AgNO3 ---> 2Ag + Cu(NO3)2

From the equation above, 1 mole of Cu reacts with 2 moles of AgNO3 to produce 2 moles of Ag and 1 mole of Cu(NO3)2.

Molar mass of the reactants and products are; Cu = 63.5 g/mol, Ag = 108 g/mol, AgNO3 = 170 g/mol, Cu(NO3)2 = 187.5 g/mol

To determine, the limiting reactant;

63.5 g of Cu reacts with 170 * 2 g of AgNO3,

19 g of Cu will react with (340 * 19)/63.5 g of AgNO3 =101.7 g of AgNO3.

Since there are 125 g of AgNO3 available for reaction, it is in excess and Cu is the limiting reactant.

63.5 g of Cu reacts to produce 108 * 2 g of Ag,

19 g of Cu will react to produce (216 * 19)/63.5 g of Ag = 64.6 g of Ag.

Therefore mass of Ag produced = 64.6g

What is Charles’s law? State the definition of the law in words. What are the assumptions of Charles’s law? Write mathematical equations that represent the law. What can you do with Charles’s law? Using a gas-filled balloon as an example, describe what happens to the gas molecules that behave according to Charles’s law.

Answers

Answer:

The volume of a given mas of a gas is directly proportional to the temperature if the pressure remains constant

V is directly proportional to T

V=1/T

V=constant/T

Explanation:

Charles law states that the volume occupied by a fixed amount of gas is directly proportional to its absolute temperature, if the pressure remains constant.

e.g., In winters as the temperature falls off, when you take a basketball outside in the ground the ball shrinks.

The mathematical equation that represents Charles law:

V₁/T₁ = V₂/T₂

where, V₁ = initial volume

T₁ = initial absolute temperature

V₂ = final volume

T₂ = final absolute temperature

The applications of Charles law has in daily life are:

Helium balloons shrinks in a cold weather.The capacity of the human lung decreases in winter season. This makes difficult for the athletes to perform in winter season and it also makes it difficult for people to go jogging.

A gas-filled balloon experiment:

If a balloon is filled with air, it will shrink when cooled and the balloon expands if heated. This happens because the air inside the balloon, which is a gas molecules, occupies a smaller volume when it is cool, and occupies  a larger volume when it is hot.

To learn more about Charles law here

https://brainly.com/question/16927784

#SPJ2

NEED HELP! An experiment _____. must always be done in a laboratory is best done if only one variable is tested for at a time can be done only by direct observation must always be done in the field

Answers

Answer:

Chemically

in chemistry

URGENT!!!!
An ordered list of chemical substances is shown.

Which substances in the list can be some of the reactants and products in the same combustion reaction? (4 points)

Select one:
a. 1, 2, and 3
b. 2, 3, and 6
c. 1, 4, and 5
d. 1, 2, and 5

Answers

Answer : The correct option is (b) 2, 3, and 6

Explanation :

Combustion reactions: It is defined as the reactions in which a hydrocarbon reacts with oxygen gas to produce carbon dioxide and water.

A balanced chemical equation is defined as the equation in which total number of individual atoms on the reactant side is equal to the total number of individual atoms on product side.

The general chemical equation for the combustion is as follows:

[tex]C_xH_yO_z+O_2\rightarrow CO_2+H_2O[/tex]

where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.

The reactants and products in the same combustion reaction are [tex]O_2[/tex] and [tex]CO_2,H_2O[/tex] respectively.

Hence, the correct option is (b) 2, 3, and 6

Other Questions
identify two current jobs that you feel humans will still be performing in 50 years and explain why robots and computers will not be performing these jobs? Round 5 to the nearest ten.Enter your answer in the box below. SOMEONE PLEASE HELP ASAP! Normal distribution models what type of variable? A.discrete random variable B.random variable C.discrete continuous variable D.random continuous variable In the inverse variation function, what happens to the output when thefunction's input value is multiplied by 4?O A. The output is divided by 2.OB. The output is multiplied by 4O C. The output is negatedO D. The output is divided by 4 Please help! Correct answer only, please! I need to finish this assignment this week. What are the dimensions of the matrix shown below? A. 3 X 15 B. 5 X 3 C. 15 X 3 D. 3 X 5 The political terms "left" and "right" owe their origin to what? The graph shows how the length of time a stroller is rented at an amusement park is related to the rental cost. what is the rate of change shown in the graph? A roller coaster glides from the rest from the top of an 80.0 m hill. What is the speed of the roller coaster at the bottom of the hill? is it a proportional relationship Which graph represents an exponential function? Which expression is equivalent to a4b2a4b4? what is the working principle of lever When light passes from a slower medium into a faster medium, which of the following explains what will occur?A.Light will not be refracted.B.Light will be refracted toward a line drawn perpendicular to the point of refraction.C.Light will be refracted away from a line drawn perpendicular to the point of refraction. Consider the scatterplot above. Write a sentence explaining the meaning of the value of the slope for this linear model. The is an average of per year . help pls!50 POINTS!! Xu owns two investments, A and B, that have a combined total value of $40,000. Investment A is expected to pay $28,000 in 3 years from today and has an expected return of 7.1 percent per year. Investment B is expected to pay $36,000 in T years from today and has an expected return of 5.5 percent per year. What is T, the number of years from today that investment B is expected to pay $36,000? "May George, beloved by all the nations round,Live with heav'ns choicest constant blessings crown'd!"Wheatley uses the word crownd to express the idea that the kingdeserves reward for his goodness.requires loyalty from other nations.requires protection from danger.deserves consideration from other nations. Assets totaled $24,750 and liabilities totaled $8,550 at the beginning of the year. During the year, assets decreased by $3,550 and liabilities increased by $2,850. What is the amount of the change in stockholders' equity during the year? write 4 1/3 as an improper fraction How was Soviet nationalism unique?A. It was sustained through economic and political hardships.B. It was more focused on religious ideology than on nationalism.C. It failed to unify the people under a common ideology.D. It was a blend of Russian nationalism and communist ideology.Please select the best answer from the choices provided. oBdCOD