Which of the answers shows three examples of a physical change

Answer:

Insulation protects you. Thats because the insulation will make a wall almost where the electrons cannot travel through. So when you touch the insulation on a live wire your SAFE. Insulations may include rubber, wood, and air.

Answer:

I'm pretty sure its insulation

Explanation:

Answer:

Wavelength, [tex]\lambda=3.64\times 10^{-10}\ m[/tex]

Explanation:

We have,

Velocity an electron is [tex]2\times 10^6\ m/s[/tex]

Mass of an electron is [tex]9.1\times 10^{-31}\ kg[/tex]

It is required to find the wavelength of electron. The De-Broglie wavelength of an electron is given by :

[tex]\lambda=\dfrac{h}{mv}[/tex]

h is Planck's constant

[tex]\lambda=\dfrac{6.63\times 10^{-34}}{9.1\times 10^{-31}\times 2\times 10^6}\\\\\lambda=3.64\times 10^{-10}\ m[/tex]

So, the wavelength of an electron is [tex]3.64\times 10^{-10}\ m[/tex].

Answer:

d. at the same velocity

Explanation:

I will assume the car is also travelling westward because it was stated that the helicopter was moving above the car. In that case, it depends where the observer is. If the observer is in the car, the helicopter would look like it is standing still ( because both objects have the same velocity). If the observer is on the side of the road, both objects would be travelling at the same velocity. Also recall that, velocity is a vector quantity; it is direction-aware. Velocity is the rate at which the position changes but speed is the rate at which object covers distance and it is not direction wise. Hence velocity is the best option.

Answer:

C. At the same speed

Explanation:

I just took the exam and got the answer correct

Answer:

D

Explanation:

Answer:

It is D

Explanation:

Because kinetic energy ALSO depends on mass (weight) so it has to be moving and has to have weight in order to be called kinetic energy.

Answer: Liquefaction occurs when the structure of a loose, saturated sand breaks down due to some rapidly applied loading.

As the structure breaks down, the loosely-packed individual soil particles attempt to move into a denser configuration. Liquefaction most often occurs when three conditions are met:

loose, granular sediment or fill

saturation by groundwater

strong shaking

Answer:

heat is applied

Explanation:with metal and ice

Answer:

Our ears perceive then sound then it is transmitted to our brain where it is processed into something we can respond to. This all happens in less than a second and we are unaware that we are doing it.  

Explanation:

The sound wave bounces off of the ear drum into the inner ear.

Answer:

Sound waves travel from the outer ear and in through the auditory canal, causing the eardrum to vibrate. This in turn causes three small bones in the middle ear to move. The vibrations move through the fluid in the cochlea in the inner ear, stimulating thousands of tiny hair cells.

Answer: I think 1 is 300 metres per second.

Explanation: wave speed= wave length x wave frequency

wave speed = 3 x 100

wave speed is 300 m/s

Answer:

See Explanation.

Explanation:

Impact metamorphism:

The process in which a rock changes because of extreme heat and pressure caused by a meteorite collision with Earth.

Regional metamorphism:

The process in which buried rocks in a large area are changed by heat, pressure, and fluids.

Contact metamorphism:

The process in which a rock changes as a result

of heat generated from magma.

Dynamic metamorphism :

The process in which a rock changes due to

pressure directed on it.

The typing of metamorphism to its best definition should be explained below.

Impact metamorphism: The process where a rock changes due to extreme heat and pressure caused by a meteorite collision with Earth.

Regional metamorphism: The process where it should be buried rocks in a large area that should be changed by heat, pressure, and fluids.

Contact metamorphism: The process where a rock changes as a result

of heat generated from magma.

Dynamic metamorphism : The process where a rock changes due to

pressure directed on it.

Learn more about pressure here: https://brainly.com/question/20772787

Answer:

not sure if this is correct but it is what i know

The metal bends more easily. The metal changes color. The metal gives off light. The metal gives off heat.

Explanation:

Answer:

negatively

Explanation:

hope this can help u :3

Answer:

negatively

Explanation:

Answer:

add energy

Explanation:

bc adding heat is energy which can make water turn into gas.

Answer:

When an object is in motion, there is energy associated with that object. Why should that be the case? Moving objects are capable of causing a change, or, put differently, of doing work. For example, think of a wrecking ball. Even a slow-moving wrecking ball can do a lot of damage to another object, such as an empty house. However, a wrecking ball that is not moving does not do any work

(hope it helps :p    )

Answer:

A.when the distance is very close from the source

Explanation:

Answerwhen the distance is very close from the source

Explanation: A

Answer:

a change from one state (solid or liquid or gas) to another without a change in chemical composition

Explanation:

Explanation:

From Solid to. Liquid to Gas A change of state is the change of a substance from one physical form to another. All changes of state are physical changes. The particles have different amounts of energy when the substance is in different states.

Answer:

[tex]Momentum(p) = 20kgm/s[/tex]

Explanation:

Given

Mass = 10kg

Velocity = 2m/s

Required

Calculate the momentum of the man

Momentum is calculated as thus

[tex]Momentum(p) = Mass(m) * Velocity(v)[/tex]

or

[tex]p = mv[/tex]

So; to solve this question; we simply substitute 10kg for mass and 2m/s for velocity in the above formula;

The formula becomes

[tex]Momentum(p) = 10kg * 2m/s[/tex]

[tex]Momentum(p) = 10 * 2 * kg * m/s[/tex]

[tex]Momentum(p) = 20kgm/s[/tex]

Hence, the momentum of the man is [tex]20kgm/s[/tex]

The correct choice is ' C '.

-- Shorter wire has less resistance than longer wire.

-- Thicker wire has less resistance than thinner wire.

-- Colder wire has less resistance than hotter wire.

The way a rock reflects light is called the luster of the rock. Hence option B is the correct answer.

When light rays bounce off one surface, transition from one transparent medium to the next, or proceed through a media whose structure is constantly shifting, they change direction.

According to the law of reflection, the angle of the reflected ray when reflecting from a level surface is the same as the angle of the ray. (By practice, all angles in wave propagation are expressed with regards to the normal to the surface, or to the line that is perpendicular to it.

The light beam and the surface normally establish a plane in which the reflected beam is always located. The pictures created by straight and curved mirrors can be understood using the

To know more about Reflection:

https://brainly.com/question/15487308

#SPJ2

Answer:

Captive animals are animals that are maintained by people in an enclosed place not allowing them to be free. There are several factors that make it difficult to reintroduce them to their natural habitats like:

-Captive animals don't learn the necessary skills to survive in their natural habitats like hunting skills.

-They are too used to have contact with people which makes them vulnerable to hunters.

-Sometimes these animals are not able to integrate with a wild population.

-It has been found that some captive animals are more susceptible to diseases.

Answer:

B

Explanation:

Heat flows from hot to cold to lower the temperature of hot areas and increase temperature of cold areas. The end result is that the 2 areas have the same temperature, thus increasing entropy.

Heat flows spontaneously from hot to cold, and entropy increases.

The second law of thermodynamics relates to the entropy of a system. According to the second law of thermodynamics, the total entropy of a system may increase or remain constant in a spontaneous process.

The implication of this is that the entropy of a system never decreases. The entropy of a system increases when heat flows from a hot to a cold body and not vice versa.

Hence, the statement that; "Heat flows spontaneously from hot to cold, and entropy increases" describes the second law of thermodynamics.

Answer:

Autism

Explanation:

Those are some symptoms of autism that you described

Answer:

Autism is the answer

Answer:

(a) The density of the object is 316/343 × the density of the oil

(b) The fraction of oil displaced after immersing the object is 0.461 of the oil volume

Explanation:

(a) The volume, V of a cone of height, h and base diameter, D = 2×r is given by the following equation;

[tex]V = \dfrac{\pi r^{2} h}{3}[/tex]

The volume of the object is therefore;

[tex]\dfrac{\pi \times 4^{2} \times 14}{3} = 74\tfrac{2}{3}\pi \, cm^3[/tex]

Where 6 cm is above the oil level we have;

[tex]\dfrac{\pi \times \left (6 \times \dfrac{4}{14} \right )^{2} \times 6}{3} = 5\tfrac{43}{49}\pi \, cm^3[/tex] above the oil level

Therefore, volume of the oil displaced = [tex]68\tfrac{116}{147}\pi[/tex] cm³ = 216.11 cm³

The density of the object is thus;

[tex]\dfrac{68\tfrac{116}{147}\pi}{ 74\tfrac{2}{3}\pi} \times Density \ of \ the \ oil = \dfrac{316}{343} \right ) \times Density \ of \ the \ oil[/tex]

The density of the object = 316/343 × the density of the oil.

(b) The volume of the oil = 2 × Volume of the object = [tex]2 \times 74\tfrac{2}{3}\pi \, cm^3 = 149\tfrac{1}{3}\pi \, cm^3[/tex]

The fraction of the volume displaced, x, after immersing the object is given as follows;

[tex]x = \dfrac{68\tfrac{116}{147}\pi}{ 149\tfrac{1}{3}\pi} = \dfrac{158}{343} = 0.461[/tex]

The fraction of oil displaced after immersing the object = 0.461 of the volume of the oil

Answer:

Waves transfer energy, not matter

Explanation:

Explanation:

No.  Centripetal force is a not a force itself, but rather a sum of forces.  From Newton's second law:

∑F = ma

∑F = m v²/r

So centripetal force does not get used on a free body diagram.

Answer: C

the emission of electrons from a metal caused by light striking the metal

Explanation:

Photo means anything related to light in Physics and science generally.

Photoelectric effect explains the effect of light incident on metal surfaces by knocking out electrons on the metal surfaces.

The correct option is C

the emission of electrons from a metal caused by light striking the metal

Answer:

The widely accepted theory for the origin and evolution of the universe is the Big Bang model, which states that the universe began as an incredibly hot, dense point roughly 13.7 billion years ago.

Answer:

Let the second medium be air (n₁=1)

The refractive index n₂ of the medium where first medium is air is found (a)

(a) n₂ = 2

Explanation:

Critical angle can be defined as the angle of incidence that provides the angle of refraction of 90°.

Refractive index of a medium can be defined as a number that describes that how fast a light will travel through that medium.

Critical angle and Refractive index are related by:

[tex]\theta_{critical}= sin^{-1}(\frac{n_1}{n_2})[/tex]

[tex]sin \theta_{critical}=\frac{n_1}{n_2}[/tex]

To find refractive index of medium with respect to air, substitute n₁=1 (Refractive index of air is 1)

Also θ(critical)=30°

Find n₂ :

[tex]sin30= \frac{1}{n_2}\\0.5=\frac{1}{n_2}\\n_2=\frac{1}{0.5}\\n_2=2[/tex]

Answer: Concave mirror and convex lens

Explanation: A spherical mirror and a thin spherical lens have each a focal length of +10cm, this means that distance of any object from the mirror is +10 metres.

While for the lens, the distance of any object to the other side of the lens is +10 metres. Therefore, the mirror is concave mirror and the lens is a convex lens.