A box weighing 450N is being pulled at an angle of 38 degrees along a
level floor. If the force applied by the rope is 260N, what is the normal
force experienced by the box (assume equilibrium)?

Answer Choices
- 160 N
- 290 N
-610 N
- 277 N

Answer:

I don't actually know, but it has to do with the research they id

Explanation:

to seem precise

The three basic rules for the electric charge are like charges repel each other, unlike charges attract each other and the charges in the system are constant. The unit of charge is coulomb (C).

Electric charge is of two types and they are positive and negative charges. The negative charge is free electrons and the positive charges are the holes in the conductors. The basic rules are, two positive charges repel each other and two negative charges repel each other and they are called like charges.

One positive and one negative charge attract each other and hence they are unlike charges. The attractional force and repulsion force increase with a decrease in the distance of separation. The charges remain constant in the system and it is called as law of conservation of charges in the system.

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A motional emf is emf = Blvsinθ, where B is the magnetic field and l is the length of the rod and v is the velocity.

By considering two cases:

1) The angle between the rod and the magnetic field, the magnetic field is separated into two components. The perpendicular component is defined by the length and velocity and the other component lying inside it. The emf is produced by the perpendicular component and the magnitude of the magnetic field is B(perpendicular) = Bsinθ. The emf is

          ε = Bvlsin(θ).

2) In the second case, the component of velocity produces the emf, and the perpendicular component is defined by the length and magnetic field. The perpendicular component of velocity, V(perpendicular) = v sinθ. The emf is,

        ε = Bvlsin (θ).

Hence, it is proved that B, v, and l are not mutually perpendicular to each other.

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Answer:

F1 = K M1 M2 / R1^2

F2 = K M1 M2 / R2^2

F2 / F1 = (R1 / R2)^2 = 1/4

The new force is 1,000,000 N / 4 = 250,000 N

The new gravitational force between the planets, when they are two million miles apart, is approximately 2.66972 × [tex]10^(-10)[/tex] N.

To solve this problem, we can use the inverse square law of gravity, which states that the gravitational force between two objects is inversely proportional to the square of the distance between them.

Let's denote the initial distance between the planets as "r1" (1 million miles) and the initial gravitational force as "F1" (1,000,000 N). The final distance between the planets will be "r2" (2 million miles), and we need to find the new gravitational force, which we'll denote as "F2."

The inverse square law formula for gravitational force is:

F = G * (m1 * m2) / [tex]r^{2}[/tex]

where:

F is the gravitational force,

G is the gravitational constant ≈ 6.67430 × [tex]10^(-11)[/tex] N m²/kg²,

m1 and m2 are the masses of the two objects (in this case, the masses of the planets), and

r is the distance between the centers of the two objects.

Since the two planets are identical, their masses are the same. Let's denote the mass of each planet as "m."

Now, we can set up two equations using the given information:

For the initial setup:

F1 = G * (m * m) / [tex]r1^2[/tex]

For the final setup:

F2 = G * (m * m) / [tex]r2^2[/tex]

Since both planets have the same mass (m), we can set these two equations equal to each other:

G * (m * m) / [tex]r1^2[/tex] = G * (m * m) /  [tex]r2^2[/tex]

Now, we can solve for F2:

F2 = (G * (m * m) / [tex]r1^2[/tex]) *  [tex]r2^2[/tex]

Substitute the given values:

F2 = (6.67430  × [tex]10^(-11)[/tex] N m²/kg² * (m * m) / (1 million mile)^2 * (2 million mile[tex]s)^2[/tex]

Note: We need to convert the distances from miles to meters before plugging into the equation. 1 mile is approximately 1609.34 meters.

r1 = 1 million miles * 1609.34 m/mile ≈ 1.60934 × [tex]10^9[/tex] meters

r2 = 2 million miles * 1609.34 m/mile ≈ 3.21868  × [tex]10^9[/tex] meters

F2 = (6.67430  × [tex]10^(-11)[/tex]  N m²/kg² * (m * m) / (1.60934  × [tex]10^9[/tex] meter[tex]s)^2[/tex]) * (3.21868 × [tex]10^9[/tex] meters[tex])^2[/tex]

Now, we see that the mass (m) cancels out, leaving us with

F2 = 6.67430 × [tex]10^(-11)[/tex] N m²/kg² * 3.21868  × [tex]10^9[/tex]  meters)^2 / (1.60934  × [tex]10^9[/tex]  meters[tex])^2[/tex]

F2 = 6.67430  × [tex]10^(-11)[/tex]  N m²/kg² * (3.21868 / 1.6093[tex]4)^2[/tex]

F2 = 6.67430  × [tex]10^(-11)[/tex]  N m²/kg² * 4

F2 ≈ 2.66972  × [tex]10^(-10)[/tex]  N

Hence, the new gravitational force between the planets, when they are two million miles apart, is approximately 2.66972 × [tex]10^(-10)[/tex]  N.

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The aforementioned statement, "Measurements must be conducted carefully to ensure that all factors—aside from the variable—are the same,” is true. Controlling for all variables besides the variable of interest is crucial when performing scientific experiments or taking measurements.

By doing so, it is possible to make sure that any observed changes or impacts are caused by the variable being monitored and not by any confounding variables.

Researchers can isolate the effects of the particular variable they are examining by maintaining the status quo for all other factors. By keeping all other conditions constant, researchers can isolate the impact of the specific variable they are studying.

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Answer: Febreze was initially not successful because it was marketed as an air freshener. At the time, people did not think their homes smelled bad, so they did not see the need for an air freshener.

Explanation:

Answer: The centripetal force acting on the car is 4752 Newtons

Explanation:

The formula for centripetal force (F) is:

[tex]F = m * v^2 / r[/tex]

where:

m is the mass,

v is the velocity, and

r is the radius.

Given that the mass (m) of the car is 990 kg, the velocity (v) of the car is 12 m/s, and the radius (r) of the curve is 30 m, we can substitute these values into the formula:

[tex]F = 990 kg * (12 m/s)^2 / 30 m[/tex]

Solving this gives:

[tex]F = 990 kg * 144 m^2/s^2 / 30 m[/tex]

This simplifies to:

[tex]F = 4752 N[/tex]

Therefore, the centripetal force acting on the car is 4752 Newtons.

B. The equivalent resistance of the two resistors is 20.0 ohms.

C. The voltmeter will measure the voltage across the 30.0 ohm resistor.

D. The 30.0 ohm resistor will stop working.

B. The total resistance of the circuit is 60.0 ohms. This is because the 30.0 ohm resistor and the 60.0 ohm resistor are in parallel, and the equivalent resistance of two resistors in parallel is equal to the product of the resistors divided by the sum of the resistors.

R_T = 1/(1/R_1 + 1/R_2 + ...)

In this case, the product of the resistors is:

30.0 ohms × 60.0 ohms = 1800 ohms,

and the sum of the resistors is:

30.0 ohms + 60.0 ohms = 90.0 ohms.

Therefore, the equivalent resistance of the two resistors is 1800 ohms / 90.0 ohms = 20.0 ohms.

C. Meter 1 is an ammeter, and it is connected in series with the 30.0 ohm resistor. This means that the ammeter will measure the current flowing through the 30.0 ohm resistor.

Meter 2 is a voltmeter, and it is connected in parallel with the 30.0 ohm resistor. This means that the voltmeter will measure the voltage across the 30.0 ohm resistor.

D. When the switch is opened, the 30.0 ohm resistor will stop working. This is because the switch is in series with the 30.0 ohm resistor, and when the switch is opened, the circuit is broken.

The 60.0 ohm resistor will continue to work, because it is in parallel with the switch, and the current will continue to flow through the 60.0 ohm resistor even when the switch is opened.

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Answer:

0.000025 m³

Explanation:

The volume of water displaced by the cylinder is equal to the volume of the cylinder itself. To find the volume of the cylinder, we need to subtract the initial volume of water in the measuring flask (200 ml) from the final volume of water with the immersed cylinder (225 ml).

Volume of displaced water = final volume - initial volume

Volume of displaced water = 225 ml - 200 ml

Volume of displaced water = 25 ml

We now need to convert this volume from milliliters (ml) to cubic meters (m³). We can use the conversion factor that 1 m³ = 1,000,000 ml:

Volume of displaced water = 25 ml ÷ 1,000,000

Volume of displaced water = 0.000025 m³

Therefore, the volume of displaced water is 0.000025 m³.

Answer:

(1) - [tex]W=20,000 \ J[/tex]

(2) - [tex]W=8.00 \times 10^6 \ J[/tex]

(3) - [tex]W=7500\ J[/tex] for part a and [tex]P=375 \ W[/tex] for part b

Conceptual:

What is work?

- Work is simply energy transferred from one place to another. Work is a scalar quantity and is measured in Joules, J.  

[tex]\boxed{\left\begin{array}{ccc}\text{\underline{Formulas used to calculate work:}}\\\\W=F\Delta r\cos\theta \ \text{(Constant} \ \vec F)\\\\W=\int\limits^{r_2}_{r_1} {F\cos\theta} \, dr \ \text{(Varible} \ \vec F)\end{array}\right}[/tex]

** "F" is the applied force on the object, "Δr" is the displacement of the object, "θ" is the measured angle between the applied force and direction of displacement. For our purposes we are assuming θ is 0, which would make the cosine equal 1.**

What is power?

- Power is the measure of work being done per second, J/s. A joule per second is a Watt, W.

[tex]\boxed{\left\begin{array}{ccc}\text{\underline{Formula used to calculate power:}}\\\\P=\frac{W}{t} \end{array}\right}[/tex]

Step-by-step:

Question (1):

Given:

[tex]F= 1000 \ N\\\\\Delta r=20 \ m\\\\Eqn\rightarrow W=F \Delta r[/tex]

Plug the known values into the equation.

[tex]\Longrightarrow W=(1000)(20)\\\\\therefore \boxed{\boxed{W=20,000 \ J}}[/tex]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Question (2):

Given:

[tex]F= 8000 \ N\\\\\Delta r=1000 \ m\\\\Eqn\rightarrow W=F \Delta r[/tex]

Plug the known values into the equation.

[tex]\Longrightarrow W=(8000)(1000)\\\\\therefore \boxed{\boxed{W=8.00 \times 10^6 \ J}}[/tex]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Question (3):

Given (part a):

[tex]F= 500 \ N\\\\\Delta r=15 \ m\\\\Eqn\rightarrow W=F \Delta r[/tex]

Plug the known values into the equation.

[tex]\Longrightarrow W=(500)(15)\\\\\therefore \boxed{\boxed{W=7500\ J}}[/tex]

Given (part b):

[tex]W= 7500 \ J\\\\t=20 \ s\\\\Eqn\rightarrow P=\frac{W}{t}[/tex]

Plug the known values into the equation.

[tex]\Longrightarrow P=\frac{7500}{20} \\\\\therefore \boxed{\boxed{P=375 \ W}}[/tex]

Thus, all given questions are solved.

The answer is C

Please dont get mad at me if this is not right im pretty sure it is
hope this helps!

Answer:

340 kg

Explanation:

F = ma

Rearranging the equation to solve for mass (m):

m = F/a

Substituting the given values:

m = 850 N / 2.5 m/s^2

m = 340 kg

Change of state due to cooling is due to the removal of thermal energy from a substance. A substance changes states, such as from a gas to a liquid or from a liquid to a solid, when its particles lose kinetic energy as it loses heat and moves more slowly. Eventually, the particles reorganize into a more ordered form with less energy. The term "solidification" or "freezing" refers to this process.

The new gravitational force between the two planets, when they are moved to two million miles apart, is 250,000 N

The gravitational force between two objects can be calculated using Newton's Law of Universal Gravitation, which states that the force is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

Given:

Initial distance between the planets = 1 million miles

Initial gravitational force = 1,000,000 N

Final distance between the planets = 2 million miles

To determine the new gravitational force, we need to compare the ratios of the distances and apply the inverse square law.

Let's denote the initial distance as d1, the initial gravitational force as F1, the final distance as d2, and the unknown final gravitational force as F2.

According to the inverse square law, the ratio of the gravitational forces is the square of the ratio of the distances:

(F2/F1) = (d1/d2)²

Substituting the given values:

(F2/1,000,000 N) = (1 million miles / 2 million miles)²

Simplifying:

(F2/1,000,000 N) = (1/2)²

(F2/1,000,000 N) = 1/4

F2 = (1/4) * 1,000,000 N

F2 = 250,000 N

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The magnitude of the electric force between the two corks is approximately 4.16 × 10^10 Newtons

We may apply Coulomb's law to determine the strength of the electric force between the two charged corks. According to Coulomb's law, the electric force between two point charges is inversely proportional to the square of the distance between them and directly proportional to the product of their charges.

Coulomb's law is expressed as F = (k * |q1 * q2|) / r2.

Where: |q1| and |q2| are the magnitudes of the charges, and r is the distance between the charges. F is the strength of the electric force, and k is the electrostatic constant (about 9 109 N m2/C2).

In this instance, the first cork's charge, |q1|, is +9.0, and the second cork's charge, |q2|, is -3.2. They are separated by r, which is 0.17.

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I have observed and experienced behaviors that are learned as a result of environmental influences, and I can furnish examples to support this assertion.

Recycling serves as a noteworthy instance. During my childhood, I acquired the habit of recycling owing to the teachings and guidance of my parents and educators, which became firmly established in me.

Water conservation serves as another illustration. Having experienced repeated droughts in my locale, I developed a sense of awareness about the utilization of water and inculcated practices such as shutting off the tap while brushing my teeth.

My daily habits have been influenced by the environmental elements in my surroundings and have now become ingrained in my routine.

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Answer:

Black's Law Dictionary defines a retroactive law as a law “that looks backward or contemplates the past, affecting acts or facts that existed before the act came into effect.” While Congress often considers legislation that would apply retroactively, the Constitution imposes some limited constraints on such laws.

The sensation of feeling cold after coming out of a swimming pool can be attributed to evaporation, conduction, individual sensitivity.

The several factors are

Firstly, water conducts heat away from the body more efficiently than air. When you are in the pool, the water absorbs heat from your body, causing you to lose heat through conduction. This lowers your body temperature, and when you step out of the water into the air, the temperature difference between your body and the surrounding environment can feel more pronounced, resulting in a sensation of coldness.

Secondly, evaporation plays a role in cooling down the body. As water evaporates from your skin's surface, it takes heat away from your body, creating a cooling effect. When you exit the pool, the moisture on your skin evaporates more rapidly in the drier air, further intensifying the cooling sensation.

Additionally, wet clothing can contribute to the feeling of coldness. Wet fabric against the skin facilitates heat transfer and can make you feel colder than if you were dry.

The perception of coldness after swimming can also be influenced by personal factors such as individual sensitivity to temperature changes, the duration of time spent in the water, and the temperature of the pool itself.

To mitigate the feeling of coldness after swimming, it is advisable to dry off and change into dry clothing promptly. Wrapping yourself in a towel or using a robe can help retain body heat. Additionally, engaging in light physical activity or seeking warmer sheltered areas can help generate body heat and alleviate the sensation of coldness.

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The expression; R vector=A vector - B vector shows that R² = A² + B² - 2ABcosθ.

Start by expanding the square of R:

R² = (A - B)²

Use the difference of squares factorization to expand this:

R² = (A - B)(A + B)

Now distribute the terms on the right-hand side:

R² = A² + AB - AB - B²

Combine like terms on the right-hand side:

R² = A² + B² - 2AB

Finally, use the cosine rule to express the magnitude of R in terms of the magnitudes of A and B and the angle between them:

R² = A² + B² - 2ABcosθ

Therefore, it is shown that R² = A² + B² - 2ABcosθ.

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Answer:

average speed = 50km/hr

average velocity =0

Explanation:

the average speed equals to average of these two speeds as the distance covered in both the cases are same.

average speed = (40+60)/2= 50km/hr

as the train returns to the same point the displacement is zero,

hence the average velocity is zero.

The average speed of the train is 50 km/hr.

The average velocity of the train is zero.

Speed of the train when it travels from the first station, v₁ = 40 km/hr

Speed of the train when it returns to the first station, v₂ = 60 km/hr

The expression for the average speed of the train is given by,

Average speed = (v₁ + v₂)/2

Average speed = (40 + 60)/2

Average speed = 100/2

Average speed = 50 km/hr

Since, the train travels from the first station, reaches the second station and then it again returns back to the first station, the total displacement covered by the train will become zero.

s = 0

Therefore, the average velocity of the train is also zero.

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a) The ratio of the slit separation to the slit width is 2.  

b) There are four bright fringes within the first side peak.

a) The ratio of the slit separation to the slit width is 2. This is because the second side peak of the diffraction envelope is located at an angle of

2λ/d, where λ = wavelength of light and d = slit width.

The diffraction minima coincide with the two-slit interference maxima, which are located at angles of λ/d.

Therefore, the ratio of the slit separation to the slit width is 2.

(b) There are four bright fringes within the first side peak. This is because the first side peak of the diffraction envelope is located at an angle of

λ/d, where λ = wavelength of light and d = slit width.

The diffraction minima coincide with the two-slit interference maxima, which are located at angles of λ/d.

Therefore, there are 4 bright fringes within the first side peak.

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The size of the angle θ of a point object moving from point A to point B along a circular path is 2πR / L.

To understand this, consider a simple example. Suppose that a point object that moves from point A to point B along a circular path with a radius of 1 meter. The distance between points A and B is also 1 meter. Therefore, the size of the angle θ is equal to 2π × 1 / 1 = 2π radians.

In general, the size of the angle θ = ratio of the circumference of the circle to the distance between points A and B. The circumference of the circle is equal to 2πR, where R = radius of the circle. Therefore, the size of the angle θ is equal to 2πR / L.

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Complete question:

A point object moves from point A to point B along a circular path with a radius R. What is the size of the angle θ?

Given that the original force is 10 newtons, the new force when the distance is doubled would be 2.5 newtons. Option A

Based on Newton's law of  gravitation, the force of gravity between two objects is inversely proportional to the square of the distance between them.

What this means is that if the distance between two objects is doubled, the force of gravity between them is reduced by a factor of four.

In this case, the distance between the two objects is doubled, so the force of gravity between them is reduced from 10 newtons to 2.5 newtons.

We can calculate it by saying 10 N / 4 = 2.5 N.

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Answer: A.

2.5 newtons

Explanation: edmentum

Electromagnetic radiation of a specific wavelength or energy is called a photon.

Electromagnetic radiation of a specific wavelength or energy is called a photon. A photon is a fundamental particle of light and is the smallest unit of electromagnetic radiation. It has no mass, but carries energy and momentum. Photons travel through space at the speed of light and can exhibit both wave-like and particle-like behaviors.The energy of a photon is directly proportional to its frequency or inversely proportional to its wavelength. This relationship is known as the Planck-Einstein equation and can be expressed as E = hf, where E is the energy of the photon, h is Planck's constant, and f is the frequency of the radiation.When a photon interacts with matter, it can be absorbed, reflected, or scattered. The energy of the photon is transferred to the absorbing material, causing an excitation or ionization of the atoms or molecules. This process is the basis for many scientific techniques, such as spectroscopy, where the absorption or emission of photons by a material is used to identify its chemical composition and structure. Understanding the properties of photons and their interactions with matter is essential for many fields of science, including optics, physics, and chemistry.

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Answer:

Explanation:

I frequency = 278 Hz

When using a dial test indicator (DTI), it is essential to ensure that the gauge is positioned at a right angle to the contact surface for accurate readings.

However, in certain situations, it may be challenging to achieve a perfect right angle alignment. In such cases, adjustments can be made to compensate for the misalignment and obtain accurate measurements.To adjust the DTI reading when the gauge is not positioned at a right angle to the contact surface, the following steps can be taken:Determine the misalignment angle: Measure the angle at which the DTI is misaligned from the right angle position. This can be done using a protractor or by estimating the deviation visually.Calculate the correction factor: Based on the misalignment angle, calculate the correction factor using trigonometric functions such as sine or cosine. The correction factor accounts for the difference between the actual displacement and the displacement measured by the DTI.Apply the correction factor: Multiply the correction factor by the DTI reading to adjust the measurement. This compensates for the misalignment and provides a more accurate reading.It's important to note that adjusting the DTI reading can introduce some degree of error, especially if the misalignment is significant. Therefore, it is always preferable to position the gauge at a right angle to the contact surface whenever possible to obtain the most precise measurements.

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Complete the following statement: A collision is elastic if...

...the total kinetic energy of the system is conserved before and after the collision, and there is no net loss of energy due to deformation or other non-conservative forces. In an elastic collision, the objects involved bounce off each other without any permanent deformation or generation of heat.

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The strongest predictor of adopting a regular exercise program is self-efficacy. Thus, Option B is correct.

      One of the best determinants of starting a regular exercise regimen is self-efficacy. Self-efficacy is a person's belief in their ability to successfully undertake a given habit, in this case, exercising on a regular basis.

People who have high self-efficacy feel they can overcome obstacles to exercise, such as a lack of time or motivation, and are more likely to persist in an exercise program.

While body mass index, self-esteem, and athleticism can all have an impact on exercise habits, self-efficacy has been proven to be an especially powerful predictor.

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Answer:

The ambient temperature is 35°C.

It takes 15 minutes to cool the substance from 40°C to 35°C.

Explanation:

Using Newton's Law of Cooling to answer the given problem.

[tex]\boxed{\left\begin{array}{ccc}\text{\underline{Newton's Law of Cooling:}}\\\\ \frac{dT}{dt} =-k(T-T_a)\end{array}\right}[/tex]

Given:

The time it takes to cool from 50°C to 45°C = 3 minutes

The time it takes to cool from 45°C to 40°C = 5 minutes

Find:

Time ambient temperature and the time it takes to cool the substance from 40°C to 35°C

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

(1) - Using first initial condition:

[tex]\text{Avg temp =} \ \frac{50+45}{2}=\boxed{47.5 \textdegree C}\\\\\Longrightarrow \frac{50-45}{3}=-k(47.5-T_a) \\\\\Longrightarrow \boxed{ \frac{5}{3}=-k(47.5-T_a)}[/tex]

(2) - Using the second initial condition:

[tex]\text{Avg temp =} \ \frac{45+40}{2}=\boxed{42.5 \textdegree C}\\\\\Longrightarrow \frac{45-40}{5}=-k(42.5-T_a) \\\\\Longrightarrow \boxed{1=-k(42.5-T_a)}[/tex]

(3) - Now we have a system of equations.

[tex]\left \{ \frac{5}{3}=-k(47.5-T_a)}} \atop {1=-k(42.5-T_a)}}} \right.[/tex]

(4) - Solve the system by dividing the top equation by the bottom equation.

[tex]\Longrightarrow \frac{\frac{5}{3}=-k(47.5-T_a)}{1=-k(42.5-T_a)} \\\\\Longrightarrow\frac{5}{3}=\frac{47.5-T_a}{42.5-T_a}\\ \\ \Longrightarrow 5(42.5-T_a)=3(47.5-T_a)\\\\\Longrightarrow 212.5-5T_a=142.5-3T_a\\\\\Longrightarrow 2T_a=70\\\\\therefore \boxed{T_a=35 \textdegree C}[/tex]

Thus, the ambient temperature is 35°C.

(5) - Find the value of "k" using either of the two previous equations

[tex]1=-k(42.5-T_a)\\\\\Longrightarrow 1=-k(42.5-35)\\\\\Longrightarrow 1=-7.5k\\\\\Longrightarrow \boxed{ k \approx -0.133}[/tex]

(6) - Now finding "dt"

[tex]\text{Avg temp =} \ \frac{40+35}{2}=\boxed{37.5 \textdegree C}\\\\\Longrightarrow \frac{40-35}{dt}=0.133(37.5-35) \\\\\Longrightarrow \frac{5}{dt}=0.3325\\\\\therefore \boxed{dt \approx15 \ min}[/tex]

Thus, it take 15 minutes to cool the substance from 40°C to 35°C.