Convert 72,390 mm to m

1,000 J of energy are needed to melt 10 g of a solid substance that is already at its melting point ,  the heat of fusion of the substance is 548 joules .

Heat of fusion, also known as enthalpy of fusion or latent heat of fusion, is the amount of energy required to melt or freeze a substance under constant pressure conditions. When it comes to chemistry, "fusion" is basically synonymous with "melting." In the classroom, heat of fusion is typically used when a substance is at its melting or freezing point. In such instances, most people consider heat of fusion to be a constant.

Water, for example, has a heat of fusion of 334 J/g at its melting point of 0°C. At 0°C, one grams  of liquid water requires 334 Joules of energy to completely freeze into ice. In addition, one grams of ice requires 334 Joules of energy to melt entirely.

q = m×∆Hf

q: Total change in heat energy (in Joules)

∆Hf: Heat of fusion of substance (in Joules per gram)

m: Mass of substance (in grams)

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Answer:

Since the center of mass is zero prior to the explosion, it must also be zero after the explosion because no external forces are present,

KE1 = 1/2 (M/2) * 50^2 m2/s^2= 25 * 2500 J = 62,500 J

The total KE will be 2 * 62,500 J = 125,000 J

The drag force acting on the car increases as the speed of the car

increases.

The correct values are;

Reasons:

The given parameters are;

Mass of the car = 2,000 kg

Engine power, P = 320 Hp = 240 kW

Inclination of the direction of motion, sin(θ) = 0.04

Speed of the car, v = 180 km/hr (50 m/s)

Losses = Air drag \(F_D\) ∝ v²

PART A Power engine exerts against gravity;

The gravitational force acting along the plane\(F_{grp}\) = m·g·sin(θ)

The power of engine against gravity, \(P_{grp}\) = \(F_{grp}\) × v

Therefore;

\(P_{grp}\) = 2000 kg × 10 m/s² × 0.04 × 50 m/s = 40,000 W = 40 kW

The power of engine against gravity, \(P_{grp}\) = 40 kW

PART B Engine power exerted against the air;

Let \(P_{pa}\) represent the engine power exerted against the air, and we have;

P = \(P_{pa}\) + \(P_{grp}\)

Therefore;

\(P_{pa}\) = P - \(P_{grp}\)

Which gives;

\(P_{pa}\) = 240 kW - 40 kW = 200 kW

Engine power exerted against the air, \(P_{pa}\) is b) 200 kW

PART C Air resistance force at the given speed

Let \(F_a\) represent the air resistance force, we have;

\(Force =\mathbf{ \dfrac{Power}{Speed}}\)

Therefore;

\(F_a = \dfrac{P_{pa}}{v}\)

Which gives;

\(F_a = \dfrac{200 \, kW}{50 \, m/s} = 4 \, kN\)

The air resistance force, \(F_a\) is b) 4 kN

PART D Power exerted by car moving on flat ground

\(F_D\) ∝ v²

\(F_D\) = k·v²

4 kN = k × (50 m/s)²

\(k = \dfrac{4 \, kN}{(50 \, m/s)^2} = 1.6 \, kg/m\)

The drag force when the car is moving at v = 25 m/s, \(F_D\) is therefore;

\(F_D\) = 1.6 kg/m × (25 m/s)² = 1,000 N

Power, P = Force × Speed

Therefore,  P = \(F_D\) × v

P = 1,000 N × 25 m/s = 25 kW

The power the car exerts, P is c) 25 kW

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The increase in the energy of an electromagnetic wave can be achieved only by decreasing the wavelength. Hence, option (d) is correct.

The given problem is based on the fundamentals of electromagnetic wave and the energy stored in an electromagnetic wave.

The mathematical expression for the energy carried out by the  electromagnetic waves is given as,

\(E = h \times \nu\\\\E = \dfrac{h \times c}{ \lambda}\)

Here,

h is the Planck's constant.

\(\nu\) is the frequency of the electromagnetic wave.

c is the speed of light.

\(\lambda\) is the wavelength of wave.

Clearly, the energy of electromagnetic waves is directly proportional to the frequency of wave and inversely proportional to wavelength. So, decreasing the wavelength, we can easily increase the energy of electromagnetic wave.

Thus, we can conclude that the increase in the energy of an electromagnetic wave can be achieved only by decreasing the wavelength. Hence, option (d) is correct.

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Answer:

Nothing can be cooled to a temperature of exactly absolute zero. The temperature of an object is a measure of the average random motion energy (kinetic energy) of its atoms. Absolute zero is the temperature at which all of an object's atoms have been brought to a dead stop relative to each other.

Explanation:

When applied to cooling, the question becomes how much work must be done and how large must the cooling reservoir be in order to cool an object to absolute zero (0 Kelvin, -273.15°C, or -459.67°F)? The physicists showed that cooling a system to absolute zero requires either an infinite amount of work or an infinite reservoir.

1. To prepare the body for the vigorous workout. 2. To allow the body to settle down and unwind. What does a well-designed kettlebell workout consist of? 1. Preparation phase: Warm up 2. Main phase: Workout 3. Final phase: Cool down What does the main phase of a workout involve?

A person’s environment can include many settings, including home, work, school, neighborhoods, recreation areas, and social events. If your environment is one in which drugs or alcohol are available and widely accepted, it can have a strong effect on your potential for abuse and addiction. Environmental factors can strongly influence addiction.

Answer:

Podemos decir que la presión que se aplica sobre un liquido encerrado en un tanque es de 5000 Pa.

Explanation:

Answer:

Podemos decir que la presión que se aplica sobre un liquido encerrado en un tanque es de 5000 Pa.

Explanation:

Answer:

Explanation:

According to Newton's Law of Gravitation, the gravitational force between two objects is always mutual, meaning that the force that one object exerts on the other is equal in magnitude but opposite in direction.

This means that if planet A exerts a gravitational force on planet B, then planet B will also exert a gravitational force on planet A. The magnitude of this force will be equal to the magnitude of the force that planet A exerts on planet B, but the direction will be opposite.

For example, if planet A exerts a gravitational force on planet B that is pulling planet B towards planet A, then planet B will also exert a gravitational force on planet A that is pulling planet A towards planet B. The magnitude of these two forces will be equal, but the directions will be opposite.

hat he sais

Answer:w

Explanation:

A fox getting its energy from a mouse and a mouse getting its energy from the grass  shows evidence of the carbon cycle

The carbon cycle is a necessary component within the global interchange between living species and the environment.

Through photosynthesis, plants absorb carbon dioxide from the atmosphere and convert it into vitalizing organic matter for consumption by animals; these organisms expend the energy obtained and consequently expel carbon dioxide back up into the air via respiration.

Moreover, when animals meet their demise and decompose, the carbon in their bodies is redeposited into Earth's soil only to eventually be delivered once again to the atmosphere through erosive activities or those generated from volcanoes.

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Answer:

Therefore, the 10 kg mass should be placed at x = 5.7 m along the x-axis to achieve a center of mass located at y = 4.5 m.

Explanation:

To find the position along the x-axis where a 10 kg mass should be placed such that the center of mass is located at y = 4.5, we can use the formula for the center of mass:

x_cm = (m1 * x1 + m2 * x2) / (m1 + m2)

Here, m1 and x1 represent the mass and position of the 8 kg mass, respectively. m2 is the mass of the 10 kg mass, and we need to find x2, its position.

Given:

m1 = 8 kg

x1 = 3 m

x_cm = unknown (to be found)

m2 = 10 kg

y_cm = 4.5 m

Since the center of mass is at y = 4.5, we only need to consider the y-coordinate when calculating the center of mass position along the x-axis.

To solve for x2, we can rearrange the formula as follows:

x2 = (x_cm * (m1 + m2) - m1 * x1) / m2

Substituting the given values:

x2 = (x_cm * (8 kg + 10 kg) - 8 kg * 3 m) / 10 kg

Simplifying:

x2 = (x_cm * 18 kg - 24 kg*m) / 10 kg

Now, we can set the y-coordinate of the center of mass equal to 4.5 m and solve for x_cm:

4.5 m = (8 kg * 3 m + 10 kg * x2) / (8 kg + 10 kg)

Simplifying:

4.5 m = (24 kg + 10 kg * x2) / 18 kg

Multiplying both sides by 18 kg:

81 kg*m = 24 kg + 10 kg * x2

Subtracting 24 kg from both sides:

10 kg * x2 = 81 kg*m - 24 kg

Dividing both sides by 10 kg:

x2 = (81 kg*m - 24 kg) / 10 kg

Simplifying:

x2 = 8.1 m - 2.4 m

x2 = 5.7 m

(brainlest?) ples:(

Answer:

the 10 kg mass should be placed at x = -2.4 m to achieve a center of mass at y = 4.5 m.

Explanation:

To find the position along the x-axis where the 10 kg mass should be placed so that the center of mass is located at y = 4.5, we can use the principle of the center of mass.

The center of mass of a system is given by the equation:

x_cm = (m1x1 + m2x2) / (m1 + m2),

where x_cm is the x-coordinate of the center of mass, m1 and m2 are the masses, and x1 and x2 are the positions along the x-axis.

Given:

m1 = 8 kg,

x1 = 3 m,

m2 = 10 kg,

y_cm = 4.5 m.

To solve for x2, we need to find the x-coordinate of the center of mass (x_cm) by using the y-coordinate:

y_cm = (m1y1 + m2y2) / (m1 + m2),

where y1 and y2 are the positions along the y-axis.

Rearranging the equation and substituting the given values:

4.5 = (83 + 10y2) / (8 + 10).

Simplifying the equation:

4.5 = (24 + 10*y2) / 18.

Multiplying both sides by 18:

81 = 24 + 10*y2.

Rearranging the equation:

10*y2 = 81 - 24,

10*y2 = 57.

Dividing both sides by 10:

y2 = 5.7.

Therefore, the y-coordinate of the 10 kg mass should be 5.7 m.

To find the x-coordinate of the 10 kg mass, we can use the equation for the center of mass:

x_cm = (m1x1 + m2x2) / (m1 + m2).

Substituting the given values:

x_cm = (83 + 10x2) / (8 + 10).

Since the center of mass is at x_cm = 0 (the origin), we can solve for x2:

0 = (83 + 10x2) / (8 + 10).

Rearranging the equation:

83 + 10x2 = 0.

24 + 10*x2 = 0.

10*x2 = -24.

Dividing both sides by 10:

x2 = -2.4.

Answer:

Explanation:

According to energy conservation which states that the workdone is equal to change in the system

Workdone = change in kinetic energy + (frictional force * distance)

Workdone = ΔK + fd

Workdone = kf-Ki + fd

Workdone = = 1/2(m(v-u)^2) + fd

Given

Mass m = 495kg

final velocity v = 105m/s

initial velocity = 0m/s

Force f= 1400N

distance d = 395m

Substitute

Workdone = 1/2(495(105-0)^2) + 1400(395)

Workdone = 2,728,687.5+553000

Workdone = 3,281,687.5 Joules

Time = 8.2secs

Power output = Workdone/Time

Power output = 3,281,687.5/8.2

Power output = 885,766.768

Power output = 8.858 * 10^5 watts

Answer:

more than 51.45 N

__________________________________________________________

We are given:

Mass of the television = 15 kg

Coefficient of Static friction = 0.35

Minimum force required to move the television:

Normal Force:

We know that the normal force is equal and opposite to the Weight of the television

Weight of the television = Mg            

[where m is the mass and g is the acceleration due to gravity]

Weight = 15 * 9.8

Weight = 147 N

Force of Friction:

We are given the coefficient of Friction = 0.35

We know that coefficient of Friction = Force of friction / Normal Force

replacing the variables

0.35 = Force of Friction / 147

Force of Friction = 147 * 0.35                     [multiplying both sides by 147]

Force of Friction = 51.45 N

Since a force of 51.45 N is will be applied opposite to the direction of application of Force, the television will only move when we apply more force than 51.45 N

Answer:

it is C

Explanation:

Answer:

1) 1.5 m/s^2

2) 4.5 N

Explanation:

From Newton's Second Law of motion, we know

\(F=m*a\)

Which states that to calculate the force acting on an object, you multiply its mass and acceleration.

So, we know an object of mass 1.5 kg has an acceleration of 3 m/s^2, then

\(F=m*a=1.5*3=4.5\)

A force of 4.5 N is acting on the object.

If a force of 4.5 N acts on a mass of 3kg we have

\(a=\frac{F}{m}=\frac{4.5}{3}=1.5\)

So, it would give it an acceleration of 1.5 m/s^2.

Answer:

The term fitness refers to the measure of reproductive success that an organism displayed; It has to do with the number of offspring that an organisms leave in the next generation compared to other organisms in the group. Populations usually evolve by natural selection. In natural selection, organisms with Inheritable traits, which help them to survive and reproduce tend to leave more children than the other organisms. Overtime, the feature that help the organisms to survive will become more common in the population and make the animals more suited to their habitats.

For the roller coaster on a frictionless track:

a. The speed of the car at Point B can be determined using the principle of conservation of energy. The total mechanical energy (sum of kinetic energy and potential energy) remains constant in the absence of external forces like friction. Therefore, if there is no energy loss, the kinetic energy at Point A is equal to the kinetic energy at Point B.

Given that the speed at Point A is 5.0 m/s, the speed at Point B will also be 5.0 m/s.

Answer: A. 5.0 m/s

b. To find the height at which kinetic energy equals potential energy, we can set the equations for kinetic energy and potential energy equal to each other.

At Point A, the roller coaster has both kinetic energy and potential energy. The total mechanical energy is the sum of these two:

Initial mechanical energy at Point A = Kinetic energy at Point A + Potential energy at Point A

At Point B, the roller coaster will have kinetic energy and potential energy, but we want to find the height at which kinetic energy equals potential energy. Let's call this height "h."

Mechanical energy at Point B = Kinetic energy at Point B + Potential energy at Point B

Since the speed at Point B is the same as the speed at Point A (5.0 m/s), the kinetic energy at both points is the same.

Equating the mechanical energy at Point A to the mechanical energy at Point B:

Initial mechanical energy at Point A = Mechanical energy at Point B

Kinetic energy at Point A + Potential energy at Point A = Kinetic energy at Point B + Potential energy at Point B

Since the kinetic energy is the same at both points, simplify the equation:

Potential energy at Point A = Potential energy at Point B

The potential energy at any point is given by the formula mgh, where m is the mass, g is the acceleration due to gravity, and h is the height.

Therefore, at the height h between Points A and B, the potential energy equals the potential energy at Point A:

mgh = mghA

Since the mass and acceleration due to gravity are the same, cancel them out:

h = hA

This means that the height where kinetic energy equals potential energy is the same as the height at Point A.

Answer: The height between Points A and B where kinetic energy equals potential energy is 5.0 m.

c. To determine if the car will reach Point C, compare the potential energy at Point B with the potential energy at Point C. If the potential energy at Point B is greater than or equal to the potential energy at Point C, the car will reach Point C.

Potential energy at Point B = mghB

Potential energy at Point C = mghC

Given that the height at Point C is 8.0 m, compare the potential energies:

Potential energy at Point B ≥ Potential energy at Point C

mghB ≥ mghC

Since the mass (m) and acceleration due to gravity (g) are constant, cancel them out:

hB ≥ hC

Therefore, for the car to reach Point C, the height at Point B must be greater than or equal to 8.0 m.

d. The minimum speed needed at Point A for the car to reach Point C can be determined by comparing the potential energy at Point A with the potential energy at Point C. If the potential energy at Point A is greater than or equal to the potential energy at Point C, the car will have enough energy to reach Point C.

Potential energy at Point A = mghA

Potential energy at Point C = mghC

Given that the height at Point A is 5.0 m, compare the potential energies:

Potential energy at Point A ≥ Potential energy at Point C

mghA ≥ mghC

Since the mass (m) and acceleration due to gravity (g) are constant, cancel them out:

hA ≥ hC

Therefore, for the car to reach Point C, the height at Point A must be greater than or equal to 8.0 m.

To summarize, for the car to reach Point C, the height at Point B must be greater than or equal to 8.0 m, and the height at Point A must also be greater than or equal to 8.0 m.

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Answer:

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

\(a = \frac{f}{m} \\ \)

where

f is the force

m is the mass

From the question

f = 8268 N

m = 1125 kg

We have

\(a = \frac{8268}{1125} \\ =7.3493 3333...\)

We have the final answer as

Hope this helps you

Soundproofing material is required for blocking sound during some works like recording voice in the studio. Image D represents the interaction of a sound wave with soundproofing material in a recording studio.

Soundproofing is done by absorbing the sound. A very much used material for this is a dense foam.

Foam and like materials absorbs sound and it travels directly into the soft surface resulting in soundproofing.

Thus, the correct option is C, as the D image is showing the absorption.

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Answer: C.D

Explanation:...

A concave mirror forming a larger, virtual image is the best interpretation of the ray diagram shown.

By splitting a hollow sphere into parts, painting the external surface, and using the internal surface as the reflecting surface, a mirror can be created. These mirrors are concave mirrors.

Light converges at a single point when it strikes and reflects back from the concave mirror's reflecting surface. The term "converging mirror" is occasionally used to describe it because of this. When the concave mirror is placed very close to the object, a magnified, upright, and virtual picture can be obtained. However, as the distance between the item and the mirror grows, the size of the picture diminishes, producing a genuine and inverted image instead. A little image may be created by the concave mirror.

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Answer:

53466kg.

Explanatiokn:

Answer:

P = 2 pi (L / g)^1/2

P2 / P1 = (8 / 2)^1/2 = 2

The period would be twice as long or 5.6 sec.

Answer:

inertia of motion

Explanation:

it's because when a passenger is jumping from a bus his/her body is in motion after falling in a road he/she remains or tends to remain in the state of motion that is the reason

Answer:  1)Scientists seek to acquire: scientific hypothesis

2)A scale measures the weight of a light object: 0.240 lbs

3)What does the process of scientific inquiry: It starts with a problem to solve or a question to answer

4)A mouse in a maze scurries 41 cm south: 76 cm southwest

5)When might an object's average velocity be equal to its average speed in two dimensions:

If the object moves in a straight line in one direction represented as positive, then the magnitude of average velocity will be equal to the average speed.

6)Using the velocity versus time graph, calculate the acceleration of Object A: 3 m/s^2

7)What is the range of a bullet fired horizontally at a height of 1.5m: 66.4m

8)What two vertical forces act on a falling leaf: weight, friction

9)What is equal and opposite to the applied force: spring force

10)Using the free-body diagram, calculate the net force: 12N, right

11)How does the force of impact during a collision change: it increases

12)The threads of a screw used to fasten two pieces of wood: by increasing the normal force exerted by the wood on the screw thread

13)A 60 kg skier with an initial velocity of 12 m/s coasts up a hill: 2.5m

14)A 1,500 kg car’s speed changes from 30 m/s to 15 m/s: -506,250 (negative 506,250| NOT POSITIVE)

15)What is true about weather: The weather depends on so many conditions that it is not possible to account for them all in any model.

16)A student records the mass of objects A, B, C, and D:  A

17)Newton’s cradle is a contraption where metal balls: friction force

18)In a closed system, an object with a mass of 10 kg: 12kgm/s

19)Given the data, what is the kinetic energy of the: 3J

20)A wedge is a simple machine that is essentially two: A length of 12 in. and a thickness of 2 in.

21)Object A and Object B are at equal distances on opposite: 3/4

22)A geosynchronous satellite has an orbital period of 24: 35,900 km

23)Calculate the eccentricity for the planet if the: 0.0167

24)A planet travels in its orbit close to apogee : the same amount of time

25)If astronomers discovered a new planet and found its: 22.3 AU

Explanation:

Hope this helps you guys!!! <3 (this is for 'A Semester Exam')

Air can do work when it exerts a force on an object and causes it to undergo displacement. The ability of air to do work is evident in various phenomena, such as wind pushing sails, fans moving objects, and air pressure powering pneumatic systems.

Air can do work through its ability to exert a force over a distance. Work is defined as the transfer of energy that occurs when a force is applied to an object and it undergoes displacement in the direction of the force. When air is in motion, it possesses kinetic energy and can exert a force on objects in its path, thus performing work.

To understand how air can do work, we can consider the example of a moving fan. When a fan is turned on, the blades start to rotate, creating a flow of air. As the air moves, it carries kinetic energy. When the moving air encounters an object, such as a piece of paper, the air molecules collide with the paper's surface and exert a force on it. This force causes the paper to move and displaces it from its initial position.

The work done by the air can be calculated using the equation:

Work = Force * Distance * cos(θ)

Where Force is the magnitude of the force exerted by the air, Distance is the displacement of the object, and θ is the angle between the direction of the force and the displacement.

In the case of air doing work on an object, the force exerted by the air is perpendicular to the direction of motion, resulting in θ = 90 degrees. Since cos(90) = 0, the equation simplifies to:

Work = Force * Distance * 0

Therefore, the work done by the air on the object is zero when the force exerted by the air is perpendicular to the displacement.

However, if the force exerted by the air is not perpendicular to the displacement, such as when blowing air at an angle to move an object, then work is performed. The air exerts a force on the object and causes it to move in the direction of the force, resulting in the transfer of energy.

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It takes 0.3 seconds for a force of 1000 N to halt a 10,000 kg goods car moving at 3.00 m/s along a track.

We must first establish the car's starting kinetic energy in order to calculate the time required to stop the vehicle:

Kinetic Energy (KE) is equal to half of mass times speed, or 10,000 kg times 3.00 m/s.

KE = 45,000 J

Then, we may use the designed with the intent, which asserts that an object's change in kinetic energy equals the jobs performed by an external force: Work equals Force x Distance x Change in KE.

The gain in kinetic energy is equal to the starting kinetic energy because the car is coming to a stop: KE Change = -45,000 J

As a result, the external force's work is: Work equals force times distance, or -45,000 J.

When we solve for distance, we obtain: Work / Force = -45,000 J / 1000 N Distance

Location = -45 m

Because the force is against the direction of the car's motion, you'll see that the range is negative.

Finally, we can calculate the travel time using the kine model for uniformly accelerated motion: Distance is equal to 1/2*acceleration*time2. Time is calculated as sqrt(2 * Distance / Acceleration) as well as sqrt(2 * 45 m / (1000 N / 10,000 kg)).

time equals sqrt(0.09 s2/kg).

time = 0.3 s

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When the ground is pulled away, the charge that the two objects have is that Object A is now negatively charged and Object B is still positively charged.

After touching object A to the ground, object A will have zero charges as it is an insulator and the ground is neutral, so no charges will flow.

Object B still has a positive charge as it is a conductor, and since object A is not connected to it anymore, there will be no transfer of charges between them.

Recall that an insulator is any property that does NOT allow electric charges to pass through them.

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The resistance band's elasticity (stretchiness) dictates how easily it can be stretched or can be flexible.

It is the proportion of tensile stress to strain, where strain is the amount of deformation and tensile stress is the tension force applied to a surface area (amount of stretch of the resistance band).

Instead than requiring you to hold additional weight per se, resistance bands function by providing an external resistance force that can be imposed. They are flat, occasionally looping bands that might be thin or thick.

Both rubber bands and springs have a unique quality. The stretch distance affects how hard a band pulls back. The spring constant, denoted by the symbol k (in units of N/m), is a proportionality constant.

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Mechanical energy changes when a roller coaster starts at a height of 40 meters and reaches a height of 20 meters. The potential energy decreases, while the kinetic energy increases.

When a roller coaster starts at a height of 40 meters and reaches a height of 20 meters, mechanical energy changes. In physics, mechanical energy is the sum of potential and kinetic energy that is present in the objects. When an object is moved, it gains or loses energy, thus the mechanical energy changes. There are two forms of mechanical energy, namely kinetic energy and potential energy. Kinetic energy is the energy that a moving object possesses due to its motion, while potential energy is the energy that an object possesses due to its position or shape.
In the case of a roller coaster, when it starts at a height of 40 meters, it has potential energy that is equal to its mass multiplied by the acceleration due to gravity multiplied by its height. As it moves down the track, the potential energy gets converted into kinetic energy, which is the energy of motion. When the roller coaster reaches a height of 20 meters, it has a lower potential energy compared to when it started. The difference in potential energy is equal to the amount of work done by the force of gravity in bringing the roller coaster down from a height of 40 meters to a height of 20 meters. At the same time, the roller coaster has a higher kinetic energy than when it started, as it gained speed during the descent.
Therefore, in summary, mechanical energy changes when a roller coaster starts at a height of 40 meters and reaches a height of 20 meters. The potential energy decreases, while the kinetic energy increases.

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The part of a road vehicle which must be tested to ensure that there is sufficient friction to stop the vehicle in an emergency is the tyre.

This is referred to as a force that resists the motion of one object against another when they roll or slide against each other.

When dealing with braking, the main factor is to have sufficient friction between the road surface and tyre to bring the vehicle to a standstill. If the tyres are wornout there won't be enough friction to make the vehicle stop during emergencies which is therefore the reason why it was chosen as the correct choice.

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The effort required to lift the load is 600N.

Based on the information given, we can use the principle of moments to calculate the effort required to lift the load. The principle of moments states that the sum of the moments of the forces acting on an object must be zero for the object to be in equilibrium.

In this case, we can write:

Effort × Effort distance = Load × Load distance

Substituting the given values, we get:

Effort × 7cm = 1680N × 2.5cm

Effort = (1680N × 2.5cm) / 7cm

Effort = 600N

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