The photograph shows a kettle made of the element copper. Which statement describes a chemical property of copper?

A. Copper forms a patina when it interacts with air.

B. Copper is a solid at room temperature.

C. Copper is a good conductor of electric current.

D. Copper can be re-shaped when hit with a hammer.

Answer:

Approximately [tex]1061\; {\rm Hz}[/tex] (rounded to the nearest whole number,) assuming that the speed of sound in the air is [tex]330\; {\rm m \cdot s^{-1}}[/tex].

Explanation:

Let [tex]v[/tex] denote the speed of this sound wave: [tex]v = 330\; {\rm m\cdot s^{-1}}[/tex] by assumption.

Let [tex]\Delta v[/tex] denote the speed at which the source (the bus) moves away from the observer (the cyclist.) In this question, [tex]\Delta v = 25\; {\rm m\cdot s^{-1}} - 5\; {\rm m\cdot s^{-1}} = 20\; {\rm m\cdot s^{-1}}[/tex].

Let [tex]d[/tex] denote the distance between the source (the bus) and the observer (the cyclist) when the first crest leaves the source. At a speed of [tex]v[/tex], it would take [tex]d / v[/tex] before the first crest arrive at the observer.

Let [tex]T[/tex] denote the period of this wave. If a crest of this wave leaves the source at [tex]t = 0[/tex], the very next one would leave at [tex]t = T[/tex]. Since the source is moving away from the observer at [tex]\Delta v[/tex], the distance between the two would have since increased from [tex]d[/tex] to [tex](d + \Delta v\times T)[/tex]. At a speed of [tex]v[/tex], this crest would now need [tex](d + \Delta v\times T) / v[/tex] to reach the observer.

In summary:

The time difference between the two crests is [tex]T[/tex] at the source. However, at the observer, this difference would have become:

[tex]\begin{aligned} &T + \frac{d + \Delta v\times T}{v} - \frac{d}{v} \\ =\; & T + \frac{\Delta v\times T}{v} \\ =\; & T\times \frac{v + \Delta v}{v}\end{aligned}[/tex].

Therefore, the ratio between the period at the source and at the observer would be:

[tex]\begin{aligned}\frac{T(\text{observer})}{T(\text{source})} &= \frac{\displaystyle T \times \frac{v + \Delta v}{v}}{T} \\ &= \frac{v + \Delta v}{v}\end{aligned}[/tex].

The frequency [tex]f[/tex] of a wave is equal to the reciprocal of its period [tex]T[/tex]. In other words, [tex]f = (1 / T)[/tex]. Therefore:

[tex]\begin{aligned}\frac{f(\text{observer})}{f(\text{source})} &= \frac{T(\text{source})}{T(\text{observer})} \\ &= \frac{v}{v + \Delta v}\end{aligned}[/tex].

Since [tex]f(\text{observer}) = 1000\; {\rm Hz}[/tex], [tex]\Delta v = 20\; {\rm m\cdot s^{-1}}[/tex], and [tex]v = 330\; {\rm m\cdot s^{-1}[/tex] by assumption:

[tex]\begin{aligned} & f(\text{source})\\ =\; & f(\text{observer}) \times \frac{v + \Delta v}{v} \\ =\; & 1000\; {\rm m\cdot s^{-1}} \times \frac{330\; {\rm m\cdot s^{-1}} + 30\; {\rm m\cdot s^{-1}}}{330\; {\rm m\cdot s^{-1}}} \\ \approx\; & 1061\; {\rm m\cdot s^{-1}}\end{aligned}[/tex].

Answer:

47.5 N

Explanation:

Given

Solving

Answer:

its light traveled through space for 1 billion years to reach us

Explanation:

Answer:

Tides and Water Levels

Explanation:

When the sun, moon, and Earth are in alignment (at the time of the new or full moon), the solar tide has an additive effect on the lunar tide, creating extra-high high tides, and very low, low tides—both commonly called spring tides

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Answer:

850m

Explanation:

The answer should be 850m

I apologize if it is incorrect-

Have a great day!

Anygays-

Answer:

saddle weighs 250 newtons. The mass of the saddle is ____250/9.8 kg______ kilograms. Use g = 9.8 N/kg for gravity.

Answer:

Acceleration

Explanation:

We know that Force = Mass * Acceleration according to the formula.

Divide both sides by “Mass” which leaves us with Force/Mass = Acceleration, in word, it’s ratio of force and mass equals acceleration.

Answer:

W=Fd

This is the equation for it

Answer:

Light travels from faraway stars to earth.

Answer:

light from a flashlight spreads out to illuminate a dark room

Explanation:

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Organic materials comes from living things while inorganic materials comes from non living things

Organic materials are those composed mainly of carbon they are derived from living things while inorganic materials are derived from non living things sucjh as rocks etc

Answer:

1000 j

Explanation:

KE = 1/2 m v^2        where m is in kg and v = m/s

    = 1/2 * .050 * (720 *1000/3600 )^2

Solar energy is a renewable energy resource that can provide suitable power for the world in general. It is one of the most abundant energy resources on Earth. Amongst the reasons why solar energy is a viable alternative energy are:

The sun is the largest source of free energy you can utilize on this planet. It can provide enough power that can supply the world’s electricity needs for a year.

One of the primary benefits of utilizing solar energy is that it can provide a clean, green source of power. It is a self-sufficient renewable energy source.

Therefore, solar energy is a viable alternative energy source because it is a renewable source of energy.

Read more on Solar energy:

https://brainly.com/question/17711999

Answer:

It has an endless supply

Explanation:

Pearson Connexus 2023.

Unlike a nonrenewable source of energy such as fossil fuels, solar power is a renewable source of energy that will not run out.

These brown dwarfs can be distinguished from other star-like objects because they exhibit absorption lines from the ammonia molecule in the spectra.

Brown dwarfs are star-like (small) objects in the external space that exhibit very low cold temperatures.

Brown dwarfs are not only small stars but also huge gaseous planets such as Saturn and Jupiter.

In consequence, brown dwarfs are a wide category that includes both planets and star-like objects.

Learn more about brown dwarfs here:

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Answer:

75000kg m/s

Explanation:

Momentum = Mass X Velocity

p = mv

3000 X 25 = 75000 kg m/s

Answer:

Gravity

Explanation:

Answer:

1, 2, and 3.

Explanation:

Hypotheses must be able to be proven false, otherwise it’s a law. It must be consistent with other theories otherwise it’s not true, and it has to be possible to prove correct, otherwise it’s a theory.

The true statement is "Falsifiable by experimental testing or observations." The correct option is 1.

In science, a hypothesis is a proposed explanation or prediction for a phenomenon or set of observations.

A new hypothesis is a fresh idea put forth by a scientist to explain a phenomenon or observation that has not been explained or understood fully by existing scientific theories or hypotheses.

The new hypothesis should be based on previous knowledge and observations, and it should be testable and falsifiable through experiments or observations. Scientists use hypotheses to guide their research and develop theories, which are more comprehensive explanations backed up by multiple lines of evidence.

Therefore, only Option (1) is the correct answer.

To learn about alternate hypotheses click:

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The distance between the sun and a planet can be gotten by measuring its orbital period and applying the Kepler's law.

According to Keplers third law; the cube of the distance between a planet and the sun is directly proportional to the square of the period of the same planet.

Having said that, we know that we can best measure the distance between the sun and a planet by measuring its orbital period and applying the Kepler's law.

Learn more about Kepler's law: https://brainly.com/question/27132799

Answer:

April

Explanation:

Answer:

Explanation:

P.E. = mgh = 7.7 * 9.81 * 20   j

Answer:

Newton's third law of motion says, "For every action there is an equal and opposite reaction." So that applied to the student's roller coaster, between the marble and the track. When the marble went up and down the hill, it created different forces onto the track.

Explanation:

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Answer:

100,000 / 800,000 = 1 / 8    amount of sample after 12 hours

(1/2)^n = 1 / 8      after n half-lives 1/8 of sample will be left

n = 3

(D) is the correct answer - 1/2 half-life = 4 hours

Hypothalamus is the region of brain is the control centre of love and also make the limbic system of our body.

The hypothalamus is the region of the brain that makes up the limbic system and is considered as the control centre of love. It gathers the various stimuli felt by the body such as smells, touches, sounds and formed the physical response to the emotions associated with those stimuli.

So we can conclude that hypothalamus is the region of brain is the control centre of love.

Learn more about love here: https://brainly.com/question/931164

Answer:

D. Protons, atoms, rock particles, bricks, buildings

Explanation:

The correct sequence that shows the units of matter from smaller to largest is option A, protons, atoms, rock particles , bricks and buildings.

The basic units of matter is called atoms. These atoms are made of subatomic particles namely, protons, electrons and neutrons. The protons and neutrons  are located inside nucleus and the electrons are revolving around.

Every substance in the universe are made of atoms. Atoms of different elements combines to form compounds. Different  solid compounds and molecules deposits to forms rocks.

Rocks can be molded to bricks and other shapes they are then used to construct buildings. Therefore, the correct sequence of the units of matter from smallest to largest is protons, atoms, rocks, bricks and buildings.

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Answer:

to ensure the safety of those in need

Explanation:

Answer:

They take a little bit to adjust to the light.

Explanation:

Because being in the dark cinema for so long, out eyes had gotten used to it being that dark while watching the movie. When we leave or go outside from it, it is a lot brighter out and our eyes arent adjusted.

Answer:

D  

Explanation:

Answer:

Explanation:

The region around a magnet in which magnetic forces can act is called a magnetic field.

Answer:

I dont know but ask a tutor

Explanation:

MOnkey Srry

Answer:

The answer is increases.

Explanation:

When positive charge is shifted from a low potential to a high potential region, the electric potential energy increases.

Explanation:

Electric potential energy directly depends upon potential region

Charge always flows from higher density to lower density in case of negative and for positive charge it's vice versa

Hence correct choice is option B