A rock is dropped from the edge of a cliff 15.0 m high. How long does it take to reach the bottom of the cliff?

4) A Mountain

The rain would run down the slopes faster than be absorbed into the rocky ground.

For this case we must do a conversion. By definition we have to:

1 inch equals 2.54 centimeters

1 day equals 24 hours.

So, we have:[tex]18 \frac {in} {day} * \frac {1} {24} \frac {day} {h} * \frac {2.54} {1} \frac {cm} {in} =[/tex]

Canceling units we have:

[tex]\frac {18 * 1 * 2.54} {24 * 1} \frac {cm} {h} =\\\frac {45.72} {24}\frac {cm} {h} =[/tex]

[tex]1,905 \frac {cm} {h}[/tex]

Answer:

[tex]1,905 \frac {cm} {h}[/tex]

Answer:

1.905cm

explanation:

The formula for mechanical energy is mechanical energy equal to kinetic energy plus potential energy

The calculation of mechanical energy is done via two components of mechanical energy, which are kinetic energy and potential energy.

Explanation:

Kinetic energy is the energy which is required to perform an action. Potential energy is the energy which the body has, just due to the virtue of being capable of doing work. Potential Energy is calculated by,

[tex]U=\boldsymbol{m} \times \boldsymbol{g} \times \boldsymbol{h}[/tex]

Kinetic energy is calculated by, [tex]K .E.=\frac{1}{2} m v^{2}[/tex]

Therefore, Energy=kinetic energy + potential energy

                      [tex]\text { Energy } E=\frac{1}{2} m v^{2}+m g h[/tex]

Answer:

solar nebula, the sun, planetesimals, inner planets, and last but not least outer planets

Answer:

1. Solar Nebula

2. The Sun

3. Planetesimals

4. Inner planets

5. Outer planets

Explanation:

A star is formed in a molecular cloud of gas and dust, mainly composed of hydrogen and helium. The Nebular Theory establishes, for the formation of the solar system, that the cloud starts to collapse under its own gravity when it receives a shock wave from a near event, for example, a supernova explosion. That results in the cloud breaking in small pieces, and those pieces constitute a possible future star.

Then it begins to accrete and rotate as a consequence of the angular momentum. In the center of that disk when it reaches the necessary temperature and pressure a protostar will born.

Around the star, in this case the Sun, fragments of dust combine until they get a meaningful size (planetesimals). According with chemical distribution on the disk of the future solar system, rocky and iron were closer to the Sun and gasses and ice were in the outer part of disk. That may explain why the inner planets are terrestrial and the outer planets are giant gasses.

the answer is D) 4 to 6 seconds

Answer:the answer is D) 4 to 6 seconds  This will help you guys

Explanation: To look at the graph

Answer:

True.

Explanation:

A scientific fact is a fact because it has been proven correct, and therefore cannot change.

Answer: 2)False

Explanation:

The scientific fact may include the statement which is based on direct observation of a scientific phenomena, scientific event or scientific process occurring in the natural world. The scientific fact is the output of what scientists believe and understand. The knowledge of scientific fact can change with the passage of time due to implementation of new methodologies, technologies and innovations.  

Answer: 800 Joules

Explanation:

The Work [tex]W[/tex] done by a Force [tex]F[/tex] refers to the release of potential energy from a body that is moved by the application of that force to overcome a resistance along a path with distance [tex]d[/tex].  

Work is a scalar, and its unit in the International System of Units is the Joule (like energy). Therefore, 1 Joule is the work done by a force of 1 Newton when moving an object, in the direction of the force, along 1 meter:  

[tex]1J=(1N)(1m)=Nm[/tex]  

Now, when the applied force is constant and the direction of the force and the direction of the movement are parallel (as this case), the equation to calculate it is:  

[tex]W=(F)(d)[/tex]

Where:

[tex]F=20 N[/tex]

[tex]d=40 m[/tex]

Then:

[tex]W=(20 N)(40 m)[/tex]

[tex]W=800 Nm=800 J[/tex]

Answer:

[tex]-5.0 m/s^2[/tex]

Explanation:

Missing question:

What is the object's acceleration?

Solution:

The acceleration of an object is given by

[tex]a=\frac{v-u}{t}[/tex]

where

v is the final velocity

u is the initial velocity

t is the time taken for the change in velocity

For the object in this problem,

u = +25 m/s

v = +15 m/s

t = 2.0 s

Substituting,

[tex]a=\frac{15-25}{2}=-5.0 m/s^2[/tex]

And the acceleration is negative because its direction is opposite to that of the velocity.

Difference between Eutrophication and Artificial Eutrophication

Eutrophication is defined as the process where there is excessive nutrients available in a water medium. There are two types of eutrophication process called as man-made eutrophication or artificial eutrophication and natural eutrophication.

As the name implies natural eutrophication occurs naturally without any external factor. Whereas artifical eutrophication is stimulated by external factor as it is forced by human activity. Eutrophication is imposed artificially so that to maintain a proper state of equilibrium is to reduce water pollution.

Eutrophication refers to the natural process of nutrient enrichment in bodies of water, while artificial eutrophication is the accelerated process caused by human activities.

1) Cause: Eutrophication occurs naturally from sources like sediment erosion and decaying organic matter. Artificial eutrophication is caused by human activities such as agriculture, sewage, and industrial discharges.

2) Rate and Timescale: Eutrophication is a slow, natural process occurring over centuries or longer. Artificial eutrophication is rapid and occurs within a shorter time frame.

3) Nutrient Sources: Eutrophication is driven by natural sources like weathering of rocks and soils. Artificial eutrophication is primarily caused by human sources such as agricultural runoff and sewage discharge.

4) Ecological Impact: Eutrophication can have ecological impacts, but artificial eutrophication often leads to more severe consequences like harmful algal blooms, oxygen depletion, and disruption of aquatic ecosystems.

5) Control and Prevention: Eutrophication is challenging to control as a natural process. Artificial eutrophication can be mitigated by implementing nutrient management practices, wastewater treatment, and land-use regulations.

In summary, eutrophication is the natural process of nutrient enrichment, while artificial eutrophication is the accelerated process caused by human activities, leading to more severe ecological impacts.

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Boron-10 and Boron-11 are isotopes of Boron. They have the same number of protons (5), but Boron-10 has 5 neutrons while Boron-11 has 6 neutrons.

Boron-10 and Boron-11 are isotopes of the element Boron, meaning they are the same element but with a different number of neutrons. Boron-10 has 5 protons and 5 neutrons in its nucleus for a total atomic mass of 10. In contrast, boron-11, has 5 protons and 6 neutrons leading to an atomic mass of 11. Both versions of boron are naturally occurring and stable, but boron-11 is slightly more abundant on Earth.

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Boron-10 and boron-11 are isotopes of boron with different masses. The average atomic mass of boron is 10.8 amu.

Boron-10 and boron-11 are isotopes of the element boron. Boron-10 has a mass of approximately 10 amu, while boron-11 has a mass of approximately 11 amu. The average atomic mass of boron is 10.8 amu, which is a weighted average of the two isotopes based on their abundance in nature.

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Answer:

Gravitational force, Weak Nuclear force, Electromagnetic force and Strong Nuclear force. The weak and strong forces are effective only over a very short range and dominate only at the level of subatomic particles. Gravity and Electromagnetic force have infinite range.

Answer:

B. Less volume than a solid state

Liquid water, in its state of matter, has more kinetic energy than when it is in a solid state, as particles move more freely in a liquid state which increases the kinetic energy.

In the three states of matter, solid, liquid, and gas, the amount of kinetic energy differs. For water, as a liquid state, it possesses more kinetic energy than in a solid state. Kinetic energy relates to movement; in a solid state, particles are tightly packed and do not move much, thus having less kinetic energy.

When it changes to a liquid state, the particles gain energy, move more freely, increasing the kinetic energy. However, the transition from solid to liquid does not affect mass or volume significantly. Thus, the correct answer is D. more kinetic energy than the solid state.

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Explanation:

Speed is defined as distance per time (miles per hour or meter per second)

Distance per time (miles per hour or meters per second) is the correct definition of speed. Option 3 is correct.

Speed is defined as the distance traveled by an object per unit of time. It represents how fast an object is moving and is typically measured in units such as miles per hour (mph) or meters per second (m/s). The correct definition of speed is "distance per time," meaning it quantifies the rate at which an object covers a certain distance in a given amount of time.

In the context of the provided options:

Option A, "distance (miles or meters)," only provides the distance traveled without considering the time taken, so it doesn't capture the concept of speed.

Option B, "time per distance (hours per mile or seconds per meter)," does not accurately represent speed; it actually represents the inverse of speed, known as the time taken to cover a unit distance.

Option C, "distance per time (miles per hour or meters per second)," is the correct definition of speed, as it directly relates the distance covered to the time taken, providing a measure of how quickly an object moves.

Option D, "time (hours or seconds)," only provides information about time and does not include the concept of distance, which is necessary to define speed.

In summary, the correct definition of speed is the rate of change of distance with respect to time, represented as "distance per time," and it is typically expressed in units like miles per hour or meters per second.

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The second object at 106 km is approximately 1.03 times further than the first object at 103 km. For proper comparison, both distances should be in the same unit, after which simple arithmetic can reveal the relation between the two.

When comparing distances, it's essential to express both measurements in the same unit to clearly understand which is greater or by how much one is greater than the other. For example, if one object is 103 km away and a second object is 106 km away, we are actually comparing two distances that are already in the same unit, kilometers. In this case, 106 km is merely 3 km farther than 103 km; it is not a multiple times further. To establish a ratio of the greater distance to the lesser one, we can divide 106 by 103, which gives us approximately 1.0291262, meaning the second object is approximately 1.03 times further away than the first object, not a whole multiple times further.

For a better understanding, let's consider the examples given:

Therefore, it's important to compare distances thoughtfully, ensuring they are expressed in the same units to accurately determine the comparison.

Answer:

The aim of Watson and Rayner was to condition a phobia in an emotionally stable child.

Explanation:

Does this help?

Final answer:

The Little Albert experiment aimed to demonstrate that fears could be conditioned through classical conditioning, challenging Freud's theory about phobias originating from internal conflicts.

Explanation:

The purpose of the Little Albert experiment conducted by John B. Watson and Rosalie Rayner was to demonstrate how emotions could be conditioned through classical conditioning. In the experiment, Little Albert was exposed to, and eventually conditioned to fear, various stimuli that were initially neutral to him, such as a white rat. The loud noise of a hammer striking a metal bar served as the unconditioned stimulus (UCS), the white rat was the conditioned stimulus (CS), the fear response to the loud noise was the unconditioned response (UCR), and the fear response to the rat was the conditioned response (CR). Through stimulus generalization, Little Albert's fear extended to other furry objects like a rabbit, a coat, and a Santa Claus mask. This experiment aimed to illustrate that phobias could be formed not by deep-seated conflicts, as Freud suggested, but through simple conditioning. The methodology and ethical considerations of this study have been widely criticized in modern times.

Answer:Newton's second law is not sufficient to explain rocket's design or requirements it also involves momentum

Explanation:by solving some equations involving newton's second law and momentum we get this Ma=mv M is mass of rocket and m is mass of gases so a=mv/M so as the time passes mass of rocket decreases due to burning of fuel and acceleration a increases

A heavier rocket requires more force to accelerate. Newton's second law, sometimes written as a=F/m, states that the heavier an object, the more force is required to accelerate it.

It implies that the time rate of change of a momentum is equal in magnitude and direction to the force applied to it. A body's momentum is equal to the product of its mass and velocity.

The amount of force produced by a rocket engine is determined by the amount of rocket fuel burned and the rate at which gas escapes the rocket (second law).

The reaction, or motion, of the rocket is equal to and in the opposite direction of the engine's action, or force (third law).

To accelerate, a heavier rocket requires more force. Newton's second law, sometimes written as a=F/m, states that the more force required to accelerate an object, the heavier it is.

Thus, this way, it could be adjusted in the design to provide more acceleration as a greater force will result in a greater acceleration, so a greater force will accelerate a rocket more.

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Answer:

Pressure

Explanation:

Let , us understand by a simple example. Let us apply some force into a needle into a cardboard what we observe , we saw that the needle get into the cardboard.

Now we will apply the same force with a water bottle into the same cardboard , now we noticed that it doesn't get buried into it.

In both examples we noticed that force applied in both the cases is equal but the surface area of the object in which force applied is different.

Here come the term pressure.

Pressure is defined as force applied per unit area.

Therefore , as area increases pressure also decreases . That's why bottle don't get buried but needle go through it.  

Force per unit area is defined as pressure, a critical concept in Physics. Measured in pascals (Pa), it refers to how force is distributed over a certain area. The smaller the area, the greater the pressure for a given force.

The term force per unit area is defined as pressure. In the field of physics, it is a prominent concept and commonly used in various studies related to fluids, gases, and solids. Pressure is typically measured in pascals (Pa), which is equivalent to a force of one newton per square meter (N/m^2).

An example that can help you understand this concept is pressing your hand against a wall. The force you're applying is spread over the area of your hand that touches the wall. If you use the same force but decrease the contact area by using just a finger, you'll feel more pressure because the same force is now distributed over a smaller area.

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Final answer:

Light exhibits wave-like properties, such as wavelength and frequency, as well as particle-like properties represented by photons, illustrating the wave-particle duality.

Explanation:

Light is characterized by its wave-like properties and particle-like properties, a concept known as wave-particle duality. As a wave, light is described by properties such as wavelength (the distance between consecutive peaks of the wave) and frequency (the number of wavelengths that pass a point in a given time).

Light's behavior as a particle is evident in phenomena like the photoelectric effect, where light is seen to consist of particles called photons.The combination of wave and particle properties provides a comprehensive framework for explaining the diverse behaviors observed in different experimental contexts.

Answer:

The work done on the box is 100 Nm

The power is 20 Nm/s

Explanation:

There is a force 25 newtons moves a box a distance of 4 meters in

5 seconds

The work done on the box is the product of the force and the distance

that the box moves ⇒ work = force × distance

The force = 25 newtons

the distance = 4 meters

Work = 25 × 4 = 100 NM

The work done on the box is 100 Nm

The force moves the box 4 meters in 5 seconds

The power is the rate of work

The power = work ÷ time

The work = 100 Nm

The time = 5 seconds

The power = 100 ÷ 5 = 20 Nm/s

The power is 20 Nm/s

The work done on the box is 100 Newton Meters and the power used is 20 Newton Meters per second.

In Physics, work done is calculated as the 'force' times the 'distance' over which the force is applied. Hence the work done in moving the box would be Work = Force x Distance = 25 Newtons x 4 meters = 100 Newton Meters (or 100 Joules, as 1 Joule = 1 Newton meter).

The 'power' is defined as the rate of doing work or the amount of work done per unit time. Hence the power would be Power = Work / Time = 100 Newton Meters / 5 seconds = 20 Newton Meters per second (or 20 Watts, as 1 Watt = 1 Joule/second).

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Answer:

Woooo more points!!!!!! Also thanks to the dude or dudette who gave the answer hope its correct

Explanation:

UHM OK ....EDIT: THE REAL ANSWER IS 3.0 x 10^8

Edit again: well my answers were different on edge but if ur from edge that’s the answer

According to Einstein, nothing in the universe can move faster than the approximate speed of light in vacuum equal to 3.0 × 10⁸ m/s.

The speed with which the light ray travels in a medium with negative pressure or in vacuum.

This speed is the greatest speed in the universe. No matter can have speed greater than the speed of light in vacuum.

Thus, nothing in the universe can move faster than which approximate speed 3.0 × 10⁸ m/s.

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Answer:

0.022

Explanation:

Answer:

o.o22

Explanation:

hope this helps

thank you say thanks to me ok

Answer: you can tell if its gold by seeing if the rock it is found in is quartz.  or you could put the gold up to a magnet, if it is real gold, it will not stick.

Explanation:

The metal piece found can be tested to clear whether it is gold or not by performing some qualitative analysis using nitric acid. If its dust dissolve in the acid, then it is not gold.

Gold is a transition metal and it is 79th element in periodic table. Gold exhibits all the metallic properties such as malleability, ductility, luster, color etc. Thus, it is widely used to make ornaments.

To test whether the yellow piece of metal is gold or not rub it on a black stone to leave a recognizable mark in order to conduct this test. Apply nitric acid to the mark after that. Any base metals that aren't genuine gold will dissolve in the acid.

Similarly  a few drops of vinegar is  applied to the item. It is not pure gold if the drops cause the metal to change hue. It is pure gold if the color remains the same.

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Answer:

Work done, W = 750 joules

Explanation:

It is given that,

Force acting on the object, F = 50 N

It moves to a distance of, d = 15 meters

We need to find the work done on an object. We know that the product of force and distance covered is called the work done. As the force and the displacement are in same direction. So,

[tex]W=F\times d[/tex]

[tex]W=50\ N\times 15\ m[/tex]

W = 750 joules

So, the work done on an object is 750 joules. Hence, this is the required solution.

Final answer:

The work done on the object is 750 joules, calculated by the formula work equals force times distance, using the given values of a 50-newton force and a 15-meter distance.

Explanation:

The work done on an object can be calculated by using the formula W = F × d × cos(θ), where W is the work done, F is the force applied, d is the distance over which the force is applied, and θ is the angle between the force and the direction of motion. Since the force and the direction of motion are the same in this case, θ = 0 degrees and cos(0) = 1, thus the equation simplifies to W = F × d. The force exerted is 50 newtons, and the distance is 15 meters, so the work done on the object is W = (50 N) × (15 m) = 750 joules.

Answer:

4800N

Explanation:

Lets assume,

Mass of first object = m₁

Mass of second object = m₂

Distance between the two objects = r

Thus the force between the two objects will be

[tex]F = \frac{G\times m_{1}\times m_{2}}{r^{2}}[/tex]

where, G = Universal gravitational constant

Given, F = 2400N

New mass of second object = 2m₂

Now, the force will be

[tex]F_{2} = \frac{G\times m_{1}\times 2m_{2}}{r^{2}}[/tex]

[tex]F_{2}= 2\frac{G\times m_{1}\times m_{2}}{r^{2}}[/tex]

[tex]F_{2}= 2F[/tex]

[tex]F_{2}= 2\times2400[/tex]

Thus, F₂ = 4800N

Answer:

The temperature and the amount of water need to be kept the same so that the only variable that changes is the surface area. If you allow the temperature and/or the amount of water to change too, you will not know which variable is causing the changes that you observe.

Explanation:

During  testing surface area, it is important to keep the temperature and the amount of water same so that can can act as control variable.

Anything kept constant or constrained in a research study is referred to as a control variable. Despite not being relevant to the study's objectives, this variable is controlled because it might have an impact on the results.

Variables can be controlled either directly by maintaining their value throughout a study (for example, by maintaining a constant room temperature in an experiment) or indirectly by using techniques like randomization or statistical control (e.g., to account for participant characteristics like age in statistical tests). Research biases like omitted variable bias can be avoided by including control variables in your analysis.

As surface area of water is changeable to the temperature and the amount of water, during  testing surface area, it is important to keep them same so that can can act as control variable.

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Answer:

The most reasonable weight for an average adult is 603 A ⇒ last answer

Explanation:

The weight of an adult = gm, where m is the mass and g is the  

gravitational acceleration

The gravitational acceleration is approximately 9.8 m/s

We need to find the most reasonable weight in units of newtons for an

average adult

The weight is 120 N

w = mg

120 = m(9.8)

Divide both sides by 9.8

m = 12.24 kg

The weight is 27 N

27 = m(9.8)

Divide both sides by 9.8

m = 2.76 kg

The weight is 1000 N

1000 = m(9.8)

Divide both sides by 9.8

m = 102.1 kg

The weight is 603 N

603 = m(9.8)

Divide both sides by 9.8

m = 61.5 kg

From the all the answers above the most suitable mass of an adult

is 61.5 kg, then the most reasonable weight for an average adult is

603 N

The most reasonable weight for an average adult is 603 A

The volume of the box is calculated by multiplying the length, width, and height given in centimeters. The volume comes out to 750.0 cm³. This converted to cubic meters (m³) gives us 0.00075 m³ or 7.5 x 10⁻⁴ m³. So the answer is D) 7.5 x 10⁻⁴ m³.

To answer your question about the volume of the box given the length, width and height in centimeters, we first need to understand that the volume is the amount of space that a substance or object occupies. In this case, the box.

The formula for volume is Volume= Length × Width × Height. So, we simply need to multiply the given measurements to get the answer in cubic centimeters (since the measurements are given in centimeters).

Let's do the math: Volume = 10.0 cm × 15.0 cm × 5.0 cm = 750.0 cm³.

However, the question asks for the volume in cubic meters (m³). To convert cubic centimeters to cubic meters, we need to know that 1m³ = 1,000,000 cm³. So, we divide our answer by 1,000,000 to get the answer in m³. Hence, 750.0 cm³ ÷ 1,000,000 = 0.00075 m³ or 7.5 x 10⁻⁴ m³. So the correct option is D) 7.5 x 10⁻⁴ m³.

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The volume of the box is given by the multiplication of length, width, and height in cm, then converted to cubic meters. The correct volume in cubic meters is 7.5 x 10^-4 m³.

The student wants to calculate the volume of a box given the dimensions in centimeters and receive the result in cubic meters. The formula for the volume of a box (or a rectangular prism) is length x width x height. So first, we calculate the volume using the provided dimensions: 10.0 cm (length) x 15.0 cm (width) x 5.0 cm (height) = 750 cm³. However, to convert this value into cubic meters (m³), we need to know that 1m³ = 1,000,000 cm³. So, we divide 750 cm³ by 1,000,000 to get 0.00075 m³. Representing this number in scientific notation will give us 7.5 x 10^ -4, which corresponds to option D.

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Answer:

Electrical force

Explanation:

Of the options given, the electric force is the only force that acts at a distance, that is, it is not necessary for two objects to be in physical contact for there to be electric force between them (Another example of force acting at a distance is the force of gravity.).

Instead, forces such as the normal force, friction force, and applied force all need contact between objects to take effect.

For example if an object does not touch the surface the normal force is null.

Answer:

55 min

Explanation:

The missing question is: how long does the trip take?

First of all, we need to find the initial distance covered by Dylan. In the first part, he rides for

[tex]t_1 = 20 min = \frac{1}{3}h[/tex]

at a speed of

v = 15 mph

therefore, the distance he covered is

[tex]d = v t_1 = (15)(\frac{1}{3})=5 mi[/tex]

Then Dylan stopped for a time of

[tex]t_2 = 5 min = \frac{5}{60}=\frac{1}{12}h[/tex]

Finally, on the way back, Dylan covered again this distance but travelling at a new speed of

v = 10 mph

So, the time he took is

[tex]t_3 = \frac{d}{v}=\frac{5}{10}=\frac{1}{2}h = 30 min[/tex]

So, the total time of the trip was

[tex]t=t_1 + t_2 + t_3 = 20 min + 5 min + 30 min = 55 min[/tex]

Dylan's bike ride involves displacement and average velocity. He ends up back at the starting point after riding a certain distance and direction with the wind and then against the wind, resulting in a final displacement of zero miles.

This question involves the concept of displacement and average velocity.

Dylan rides his bike east for 20 minutes at a speed of 15 mph. The distance he travels can be calculated by multiplying the speed by the time: (15 mph) x (20 min) = 300 miles. Since he rides in a straight line, his displacement is also 300 miles east.

After turning around and riding back, Dylan travels at a speed of 10 mph. In the opposite direction, his displacement will be the negative value of his initial displacement: -300 miles.

Overall, his final displacement is the sum of his initial displacement and his opposite displacement: 300 miles + (-300 miles) = 0 miles. This means that Dylan ends up back at the starting point, 48th Street.

Answer:Physical changes involve states of matter and energy.

Explanation:

No new substance is created during a physical change, although the matter takes a different form. The size, shape, and color of matter may change. Physical changes occur when substances are mixed but don't chemically react.

Final answer:

A physical change is when matter changes its form or properties without changing its chemical identity, such as melting ice or evaporating water.

Explanation:

A physical change is a type of change in which the form of matter is altered but its identity remains the same. For example, when an ice cube melts, it goes from a solid to a liquid (Figure 1.2.3); this change alters its shape and allows it to flow, yet the chemical composition of water (H₂O) does not change. Another instance is when water vaporizes; the temperature and energy of water molecules increase leading to evaporation, turning liquid water into water vapor (H₂O (l) → H₂O (g)), without altering the molecular structure.

Sorting a mixture of pennies and nickels changes the arrangement of the coins without changing their properties. Similarly, tearing a piece of paper changes its shape and size, but it remains paper. These examples show that during a physical change, the arrangement of particles may change, but the mass, number of atoms, and number of molecules stay the same.