A roller coasters velocity at the top of a hill is 21mls. Two seconds later it reaches the bottom of the hill with a velocity of 36mls. What is the acceleration of the roller coasters

Answers

Answer 1

Answer:

7.5 m/s²

Explanation:

The following data were obtained from the question:

Initial velocity (u) = 21 m/s

Final velocity (v) = 36 m/s

Time (t) = 2 secs

Acceleration (a) =..?

The acceleration of an object is simply defined as the rate of change of velocity of the object with time. Mathematically, it is represented as:

Acceleration (a) = (final velocity (v) – initial velocity (u)) / time (t)

a = (v – u)/t

With the above formula, we can determine the acceleration of the roller coaster as follow:

a = (v – u)/t

a = (36 – 21)/2

a = 15/2

a = 7.5 m/s²

Therefore, the acceleration of the roller coaster is 7.5 m/s².


Related Questions

The structures found in a living cell can be compared to the parts of a factory that produces cars. Which part of the factory is most similar to the nucleus of a living cell? *

Answers

The computers that help control the machines in the factory

How would you measure the mass and weight of an object?

Answers

Answer:

Weight = mass × earth's gravitational acceleration

Explanation:

Follow the following steps to measure the mass and weight of an object:

Measure the mass of the object using an accurate measuring scale.Multiply the mass of that object with earth's gravitational  acceleration which is approximately 9.8 N/kg

Magnesium unites completely and vigorously with oxygen to form magnesium oxide, which contains 60% magnesium by weight. If 1.00 gram of magnesium is sealed in a glass tube with 1.00 gram of oxygen, what will be present in the tube after the reaction has taken place

Answers

Answer:

After the reaction, there will 0.60 g of magnesium oxide and 0.25 g of oxygen gas present in the tube

Explanation:

Equation of the reaction between magnesium and oxygen is given as follows:

2Mg(s) + O₂(g) ---> 2MgO(s)

From the equation of reaction, 2 moles of magnesium reacts with i mole of oxygen gas to produce 1 mole of magnesium oxide

molar mass of magnesium is 24.0 g; molar mass of oxygen gas = 32.0 g; molar mass of magnesium oxide = 40.0 g

Therefore 24 g of magnesium reacts with 32 g of oxygen gas

I.00 g of magnesium will react with (24.0 / 32.0) * 1.00 g of oxygen = 0.75 g of oxygen gas.

Therefore, magnesium is the limiting reagent. Once it is used up, the reaction will stop and the excess oxygen will be left in the tube together with the product, magnesium oxide.

mass of excess oxygen = 1.00 - 0.75 = 0.25 g

mass of magnesium oxide formed = (24.0 / 40.0 g) * 1 = 0.60 g

You are given a mixture of sand, sugar and sulphur. Give the method you will use to separate the three constituents. ___________

Answers

Answer:

1:put these in sneaker and add water since sulphur is insoluble and the sugar will dissolve and the sand will settle obtain the sulphur

2:filter the mixture of sand and sugar solution to obtain the sand as residue and solution as filtrate

3:using an evaporating dish evaporate sugar solution to saturation not dryness to get crystals.

Why does this experiment need a water pump?

Answers

Answer:

because the water/air needs to be pumped out.

Explanation:

hoped this helped! (just give it a 1 star if it didn't)

Which of the following choices would have a negative entropy change? A. CaCO3(s)−>CaO(s)+CO2(g)

Answers

Answer: N2(g) + 3H2(g)- >2NH3(g) denotes a negative entropy change.

Explanation:

Entropy is defined as the extent of disorder in a system. The degree of entropy is more in a gas and less in a solid.

Here, 1st reaction produces ammonia from nitrogen and hydrogen. We can see that four moles of gases produces 2 moles of gaseous product. So the degree of disorder in the system is decreasing. So the entropy is also decreasing.

How does increasing temperature increase the number of reactions

Answers

Answer:

A

Explanation:

the increase in the temperature let's the particles to collide more so it increases the rate of reaction.

Answer:

I think the answer is option A.

Explanation:

Because when the temperature increases, the kinetic enegry increases which creates the effective collisions which lets the chemical to react.

Hope it helps..

For which of the following reactions will a decrease in pressure shift the equilibrium to the left?
A). 2A2 (g) + B2 (g) --> 2A2B (g)

B). 2AB (g) --> A2 (g)+ B2 (g)

C). 2A2F3 (g) --> 4A (g) + 3F2 (g)

D). 2B (s) + 2HA (aq) --> 2BA (aq) + H2 (g)

Answers

Answer: I just took the test, the answer is A.

Explanation:

Which of the following would NOT be a conversion factor for mole to mole calculations for the following reaction: 2Al + 3Cl2 --> 2AlCl3
A: 3 mol Cl2 3 mol Al
B: 2 mol Al 3 mol Cl2
C: 2 mol AlCl3 2 mol Al
D: 3 mole Cl2 2 mol AlCl3

Answers

Answer: A. 3 mol [tex]Cl_2[/tex] 3 mol Al:

Explanation:

Te given balanced chemical equation is :

[tex]2Al+3Cl_2\rightarrow 2AlCl_3[/tex]

According to the stochiometry :

A: 3 mol [tex]Cl_2[/tex] 3 mol Al:

3 moles of chlorine reacts with 2 moles of aluminium

B. 2 mol [tex]Al[/tex] 3 mol [tex]Cl_2[/tex]:

2 moles of aluminium  reacts with 3 moles of chlorine

C.  2 mol [tex]AlCl_3[/tex] 2 mol Al

2 mol of aluminium produces 2 mol of [tex]AlCl_3[/tex]

D. 3 mol [tex]Cl_2[/tex] 2 mol [tex]AlCl_3[/tex]

3 moles of chlorine produces with 2 moles of [tex]AlCl_3[/tex]

Thus the conversion factor not used for mole to mole calculations is  3 mol [tex]Cl_2[/tex] 3 mol Al:

Label the following as either an Element, Compound, or Mixture.

Answers

Answer:

27. Element (Because it contains all same atoms)

28. Compound (It contains atoms held together through chemical bonds)

29. Element (it contains all same atoms)

33. Mixture (It contains different atoms but they are not held together through chemical means)

34. Compound (Different atoms held together through chemical means)

35. Mixture (Mixture of elements and compounds)

30. Element (it contains all same atoms)

31. Mixture (Mixture of elements and compounds)

32. Element (Contain all same atoms although held together through chemical means they are not compounds)

When the name of ions end with ide, is it true that they are all negative ions

Answers

Yes, from all the examples I can think of
Negative: Chloride, Bromide, Iodide
Positive: Sodium, Silver, Mercury

​Ascorbic Acid is a organic compound with formula C6H8O6, originally called Hexuronic Acid. It's a white solid, but impure samples can be yellowish. It dissolves well in water to give mildly acidic solutions. It is a mild reducing agent.

What is the other name of Ascorbic Acid?

Answers

Explanation:

ascorbic acid is lemon

lemon contain ascorbic acid....

it is organic acid.....

Which type of river is similar to a mature river, but flows more slowly so has less power to change the landscape? Select one: a. Youthful River b. Mature River c. Old Age River

Answers

Answer:

The correct option is;

C. Old Age River

Explanation:

Among the three stages of  the development of a river, which are the youthful, mature, and old age stages, the old age river is least dynamic

The water is very slow moving  with a low gradient and lesser erosive power to alter the landscape which results in the appearance of flood planes

Examples of old age rivers include, lower Ganges, lower Nile, Indus, and Yellow rivers

Old age rivers are characterized by a broad shape, with a wide flood plane, a very gentle gradient and the water current is low.

Answer:c

Explanation:

old age river

Below are 5 sets of potential solutes for you to compare. Both members of each pair are very soluble in water. If you had equal molar concentrations of each solution, which member of each pair would theoretically be the better conductor of electricity?
A. CsCl, CaCl2.
B. CaS, Li2S.
C. KBr, AlCl3.
D. AlCl3, MgC2.
E. KI, K2S.

Answers

Answer:

Option D. AlCl₃, MgC₂

Explanation:

We need to dissociate all the salts, to determine the i. (Van't Hoff factor).

The salt who has the highest value, will be the better conductor of electricity

CsCl  → Cs⁺  +  Cl⁻   i = 2

CaCl → Ca²⁺ +  Cl⁻   i = 2

CaS → Ca²⁺ +  S⁻²    i = 2

Li₂S → 2Li⁺  +  S⁻²    i = 3

KBr →  K⁺  +  Br⁻       i = 2

AlCl₃ →  Al³⁺ + 3Cl⁻   i = 4

MgC₂  →  Mg²⁺  +  2C⁻   i = 3

KI  →  K⁺  +  I⁻     i = 2

K₂S  →  2K⁺  + S⁻²   i = 3

The biggest i, is in pair D.

Answer:

Look at the Screenshot!!!

Explanation:

Got it right on Odessyware ;) Have a nice day!!!!!

Which statement accurately describes a light-year

Answers

Answer:

B. distance light travels in a year

got it on edge :)

The statement which accurately and best describes a light-year is the total distance which light travels in a complete year

What is velocity of light?

Velocity of light can simply be defined as that fundamental constant that represents the speed of electromagnetic radiation in a vacuum.

The velocity of light = 2.9979 × 10^10cm/s

So therefore, the statement which accurately and best describes a light-year is the distance which light travels in a complete year

Learn more about light-year:

https://brainly.com/question/1224192

#SPJ2

show bond formation in magnesium chloride​

Answers

mg has a 2 in its valence shell

it will become mgcl2

. . . .

: Cl -------- Mg ------ Cl :

. . . .

How many moles of ZnCl2 will be produced from 61.0 g of Zn, assuming HCl is excess?

Answers

Answer: 0.938 moles of [tex]ZnCl_2[/tex] will be produced.

Explanation:

To calculate the moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]

moles of zinc:

[tex]\text{Number of moles}=\frac{61.0g}{65g/mol}=0.938moles[/tex]

[tex]Zn+2HCl\rightarrow ZnCl_2+H_2[/tex]

As HCl  is in excess , zinc is the limiting reagent and it limits the formation of product.

According to stoichiometry :

1 mole of Zn produce =  1 mole of [tex]ZnCl_2[/tex]

Thus moles of  Zn produce = [tex]\frac{1}{1}\times 0.938=0.938[/tex] moles of [tex]ZnCl_2[/tex]

Thus 0.938 moles of [tex]ZnCl_2[/tex] will be produced.

Seawater is highly saline, which means it contains large amounts of dissolved salt. When seawater freezes and icebergs form, the water in the iceberg doesn’t take the salt with it. What effect will this phenomenon have on the concentration of salt in the water around the iceberg?

Answers

Answer:

Because the amount of liquid water decreases and the amount of dissolved salt remains constant, the concentration of salt in the liquid water around the iceberg will increase.

Explanation:

Answer:

Because the amount of liquid water decreases and the amount of dissolved salt remains constant, the concentration of salt in the liquid water around the iceberg will increase.

Explanation:

PLATO exact answer

g When a 2.75g sample of liquid octane (C8H18) is burned in a bomb calorimeter, the temperature of the calorimeter rises from 22.0 °C to 41.5 °C. The heat capacity of the calorimeter, measured in a separate experiment, is 6.18 kJ/°C. Determine the ΔE for octane combustion in units of kJ/mol octane.

Answers

Answer:

The correct answer is 5021.25 kJ/mol octane

Explanation:

The heat absorbed by the calorimeter is given by:

heat absorbed = Ccal x ΔT

Given:

Ccal = 6.18 kJ/ºC (heat capacity of calorimeter)

ΔT= Final temperature - initial temperature = 41.5ºC-22.0ºC = 19.5ºC

We first calculate the heat absorbed:

heat absorbed = 6.18 kJ/ºC x 19.5ºC = 120.51 kJ

The change in internal energy (ΔE) is equal to the heat absorbed by the calorimeter. In order to determine ΔE in kJ/mol we have to divide the heat into the number of moles of octane (C₈H₁₈) burned in the calorimeter.

Molecular weight (C₈H₁₈) = (12 g/mol x 8) + (1 g/mol x 18) = 114 g/mol

Moles of C₈H₁₈= mass/molecular weight= (2.75 g)/(114 g/mol)= 0.024 moles

Finally, we calculate ΔE:

ΔE = heat absorbed/moles of octane = (120.51 kJ)/(0.024 mol octane) = 5021.25 kJ/mol octane

What letter represents the enthalpy of reaction?

Answers

Answer:

Option D. T

Explanation:

Enthalpy change (ΔH) is simply the difference between the heat content of the product (Hp) and the heat content of the reactant (Hr). Mathematically, it is expressed as:

Enthalpy change (ΔH) = Heat of product (Hp) – heat of reactant (Hr)

ΔH = Hp – Hr

From the diagram given above, the difference between the heat content of product and the heat content of reactant is T.

Therefore, the enthalpy change of the reaction is T.

Describe the crystallization process as applied in salt preparation

Answers

Explanation:

The principle used in the preparation of these salts is to dissolve

the cystine in an alcoholic alkali solution to which just sufficient

water to effect solution has been added, and, after filtering from

excess cystine, to precipitate the salt by addition of a suitable

indifferent solvent. While various solvents, such as acetone,

ether, or large amounts of alcohol caused precipitations, these were

either oily or amorphous. Only acetonitrile was found to possess

the power of initiating regular crystallization in the salt solutions.

While the solutions of the different salts require different amounts

of the solvent for complete precipitation, a partial substitution of

absolute ether for acetonitrile was found expedient in the case

of the most soluble of the salts, the K salt.

Answer:

It is simply a process of forming crystal.

Explanation:            When salt is heated and dissolve in the liquid mainly water then its called saturated solution. When we further add salt and increase heat in order to dissolve it then it forcibly dissolve in liquid it's called supersaturated solution. After we slowly cool down the temperature then the salt we have put in supersaturated solution arises in the form of crystal. Hence its called crystalization.

A 35 gram of saturated solution is distilled out completely. If the solubility of the solute is 110, find the amount of residue solute snd distilled water

Answers

Answer:

3850g

Explanation:

Solubility is the amount of solute dissolved in a solvent.

Solubility is mass of solute÷mass of solvent

The solvent is 35grams

Solute?

Solubility of solute is 110

110=x/35

= 110 × 35

The amount of residue solute is 3850g

Q2.
For the reaction given, how many litres of carbon dioxide gas will be formed by the reaction of 400
litres of oxygen with sufficient pentene (CH..)? The reaction takes place at 125°C and 10.5 atm.
2 C5H10(1) + 15 O2(g) →10 CO2(g) + 10 H20 (8)

Answers

Answer:

266 liters Carbon iv oxide will be formed

Explanation:

The first thing we need to do here is to calculate the number of moles of oxygen reacted.

This can be calculated using the ideal gas equation;

Mathematically;

PV = nRT

From the question;

P = pressure = 10.5 atm

V = volume = 400 liters

n = number of moles = ?

T = temperature = 125 + 273 = 398K

R = molar gas constant = 0.0821 L•atm•K^-1•mol^-1

Substituting these values, we have ;

n = PV/RT

n = (10.25 * 400)/(398 * 0.0821) = 125 moles

From the question;

15 moles oxygen gave 10 moles CO2

125 moles oxygen will give x moles CO2

x = (125 * 10)/15 = 83 moles

Now, we want to know the volume of CO2, present in 83 moles using the given reaction conditions.

Mathematically;

PV = nRT

V = nRT/P

= (83 * 0.0821 * 398)/10.25 = 265.65 which is approximately 266 Liters

Select the correct answer.
What is the reason for heat transfer from one substance to another

Answers

Answer:

Difference in temperature.

Explanation:

Conduction is the movement of heat energy through a substance or from one substance to another by direct contact of atoms and molecules. Heat moves directly from one molecule to another. The heat energy speeds up the movement of the atoms and they collide with other molecules setting them into faster motion.

Two oxides of lead were separately reduced to metallic lead by heating in a current of

i) Mass of yellow oxide taken=3.45g

ii) Mass of brown oxide taken=1.227g
Loss in mass during reduction=16g

Show that the above data illustrate the law of multiple proportions.​

Answers

Answer:

HeyA ❤

Let us consider the mass of oxygen as 1 g.

Mass of lead obtained from yellow oxide = 3.45 g – 0.24 g = 3.21 g

Mass of oxygen = 0.24 g

The mass of lead that combines with 0.24 g of oxygen = 3.21 g

Therefore, mass of lead that combines with 1 g of oxygen = 3.21/ 0.24 = 13.4 g

Mass of lead obtained from brown oxide = 1.227 g – 0.16 g = 1.067

Mass of oxygen = 0.16g

The mass of lead that combines with 0.16 g of oxygen = 1.067 g

Therefore, mass of lead that combines with 1 g of oxygen = 1.067/ 0.16 = 6.66 g

Now, ratio of masses of lead which combines with a fixed mass of oxygen = 13.4 : 6.66

= 2 :1

Thus, masses of lead which combine with the fixed mass of oxygen are in the ratio of (2:1) i.e. small whole numbers.

Hence, the law of multiple proportions is illustrated.

Follow meehhhh Piper ❤

Which metal will react spontaneously with Cu2+ (aq) at 25°C?

Hg

Mg

Ag

Au

Answers

Answer:

Mg  

Explanation:

The standard reduction potentials are

                                              E°/V

Au³⁺(aq ) + 3e⁻  ⟶  Au(s);     1.42

Hg²⁺(aq)  + 2e⁻  ⟶  Hg(l);     0.85

Ag⁺(aq)    +   e⁻  ⟶  Ag(s);    0.80

Cu²⁺(aq)   + 2e⁻ ⟶  Cu(s);   0.34

Mg2+(aq) + 2e- ⟶  Mg(s);   -2.38

The more negative the standard reduction potential, the stronger the metal is as a reducing agent.

Mg is the only metal with a standard reduction potential lower than that of Cu, so

Only Mg will react spontaneously with Cu²⁺.

 

Answer:

B. Mg

Explanation:

Which of the following may suggest a catalyst has been used in a reaction, given the energy diagram for the same reaction without a catalyst?

Answers

The answer I think would be C

The temperature of a sample of liquid water changes from 50°C to 30°C. Which statement best explains the change
that must happen at the molecular level?
ОООО
The molecules move more quickly and their average kinetic energy increases.
The molecules move more slowly and their average kinetic energy decreases.
The molecules move more quickly and their average kinetic energy decreases.
The molecules move more slowly and their average kinetic energy increases.

Answers

Answer:

The molecules move more slowly and their average kinetic energy decreases

Explanation:

The increased temperature meant that the atoms in liquid had a greater average energy of motion so as the temperature decreases the reaction would be inverse.

The branch of science which deals with the chemicals bond is called chemistry.

The correct option is B.

The energy which is produced by the motion of the particles is called kinetic energy. Temperature increases the motion of the particles. So, the kinetic energy increases when the temperature rises.

According to the question, the temperature of the water decreases therefore the kinetic energy decreases.

Hence, the correct option is B that is the molecules move more slowly and their average kinetic energy decreases.

For more information, refer to the link:-

https://brainly.com/question/25026730

The freezing point of pure chloroform is -63.5°C, and its freezing point depression constant is 4.07°C•kg/mol. If the freezing point of a solution of benzoic acid in chloroform is -70.55°C, what is the molality of this solution? 0.58 m 1.7 m 16 m 17 m

Answers

Answer: The molality of this solution is 1.7 m

Explanation:

Depression in freezing point:

[tex]T_f^0-T^f=i\times k_f\times m[/tex]

where,

[tex]T_f[/tex] = freezing point of solution = [tex]-70.55^0C[/tex]

[tex]T_f^0[/tex] = freezing point of pure chloroform = [tex]-63.5^0C[/tex]

[tex]k_f[/tex] = freezing point constant of benzene = [tex]4.07^0Ckg/mol[/tex]

m = molality

i = Van't Hoff factor = 1 (for non-electrolyte)

[tex]-63.5-(-70.55)^0C=1\times 4.07^0Ckg/mol\times m[/tex]

[tex]7.05=1\times 4.07^0Ckg/mol\times m[/tex]

[tex]m=1.7[/tex]

Thus the molality of this solution is 1.7 m

Easyyyyy plz ...................

Permanent hardness of water is caused by dissolved :-
A) CaCl
B) Ca(HCO3)2
C) Mg(HCO3)2
D) NaOH​

Answers

Answer:

The answer is B

Explanation:

Answer:

Hello!

Your answer is B) Ca(HCO3)2!!

Explanation:

Hope this helps you!!

itsMATT04

:>

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The coefficient associated with heat transfer by natural convection between the person and the room air is approximately 2 W/m2 Middot K. DeLong Corporation was organized on January 1, 2017. It is authorized to issue 14,500 shares of 8%, $100 par value preferred stock, and 450,000 shares of no-par common stock with a stated value of $3 per share. The following stock transactions were completed during the first year.Jan. 10 Issued 84,500 shares of common stock for cash at $6 per share.Mar. 1 Issued 5,150 shares of preferred stock for cash at $110 per share.Apr. 1 Issued 23,500 shares of common stock for land. The asking price of the land was $91,000. 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