Which characteristic is not a characteristic of plastic?
1.easy to mold
2.good conductor of heat
3.lightweight and durable
4.repels water

The kayaker needs to paddle at an angle of 41.81º opposite to the current so that he can travel straight across the harbor, and it will take him 44.73 seconds to cross.

This is a 2-dimensional problem, since the kayaker can move in 2 dimensions over the river. For our study, we will model how does the kayaker move in the direction transversal to the river (meaning across the river), and longitudinal to the river (meaning along the river).

On the first part of this problem, we're asked to compute the direction at which the kayaker needs to paddle so that he moves only transversal to the river flow. Since the river flow has a velocity of 2 meters per second on the longitudinal direction, then the kayaker must have a velocity opposite to the river flow on the longitudinal direction of 2 meters per second.

Since he can paddle with a speed of 3 meters per second, we can make a right triangle (check the attached figure), and through trigonometry find the angle at which he needs to paddle against the river to only move in the transversal direction. Therefor we can write:

[tex]sin(\theta) = \frac{2}{3}[/tex]

Therefor [tex]\theta[/tex] is 41.81 degrees. This means that the kayaker moves across the river with a velocity 2.24 meters per second. With this velocity and the width of the river, we can easily find that the time it will take to cross is 44.73 seconds.

Right triangle, velocity, sine of angle.

Answer: from 21 km/h to 31 km/h

Explanation: The more speed it has the more kinetic energy it is required for it to go faster.

Tensile force refers to the stretching force experienced when forces pull on both ends of a material like wire. Equal and opposite forces lead to tension that is equally distributed across the material, as seen in Figure 5.24. The example of a tightrope walker underscores that most of the tension resides in the wire itself rather than supporting the walker's weight.

In Physics, the term tensile force is used to describe the stretching force a material experiences when forces are applied on opposing sides, such as a wire being pulled on both ends. In your case, the brass wire has to withstand a tensile force of 350N without breaking.

Considering the principles behind tensile force, the concept of equal and opposing forces holds significant value as depicted in Figure 5.24. This is due to Newton's third law which states that every action has an equal and opposite reaction, ensuring that the tension in the wire is equal throughout. If the tension at one spot in the brass wire could handle 350N, this could be applied across the entire wire.

The tightrope example illustrates a situation where the tensile force is employed. However, not all this tension is used to support the weight of the tightrope walker as the horizontal components are in opposite directions and cancel out. Hence, most of the tension resides in the wire itself.

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The Earth has the strongest magnetic field among the terrestrial worlds due to its partially molten metallic core and rapid rotation. These factors create convection currents and electric currents that generate the magnetic field.

The Earth has the strongest magnetic field among the terrestrial worlds because it is the only one that has both a partially molten metallic core and reasonably rapid rotation. These two factors are essential for generating a magnetic field through a process called the dynamo effect.

The Earth's molten, iron-rich outer core and its rotation create convection currents that generate electric currents, which in turn produce a magnetic field.

By having a partially molten metallic core, the Earth is the only terrestrial world capable of generating a magnetic field. Other terrestrial worlds, such as the Moon or Mars, have solid cores and lack the necessary convection currents to generate a magnetic field.

Additionally, the Earth's reasonably rapid rotation helps sustain its magnetic field. The rotation of the Earth causes the convection currents in the outer core to twist and rotate, which further amplifies the magnetic field strength.

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Explanation:

While driving on the road we should be alert and cautious at every point of driving. We should also follow the basic traffic rules for ours as well as others safety.  So when passing by a large truck, we should make sure that we see a lot of the pavement area in front of the truck so that we are aware of the fact that there is enough space in front of the truck for us to apply brake and halt our car incase if there is any danger ahead. And also if the truck happens to stop suddenly, we get enough space to stop for our safety. Also to see if there is any obstacles ahead so that we do not hit the obstacle and meet with accidents.  

The final temperature of the mixture is 48.33° C.

The term "temperature" describes how hot or cold a body is. It is, specifically, a method of calculating the kinetic energy of the particles that make up an item. When particles move more quickly, the temperature rises, and vice versa.

Given parameters:

Volume of the water at 25.00° C, V₁ = 240.0 mL.

Volume of the water at 95.00° C, V₂ = 120.0 mL.

The density of water, ρ = 1.00 g/mL

Then, final temperature, t = ?

Mass of the water at 25.00° C, m₁ = V₁ρ = 240.0× 1 g = 240.0 g.

Mass of the water at 95.00° C, m₁ = V₁ρ = 120.0× 1 g = 120.0 g.

We know that, specific heat of water, s =1 CGS unit.

Then, the amount of heat energy absorbed by the water at 25.00° C to reach final temperature (t), is H₁ = m₁s(t-25) Joule =240(t-25) Joule.

And the amount of heat energy dissipated by the water at 95.00° C to reach final temperature (t), is H₂ = m₂s(95 - t) Joule = 120 (95 - t) Joule.

From the conservation of heat energy,

H₁ = H₂

⇒ 240(t-25) = 120 (95 - t)

⇒ 2(t -25) =(95 -t)

⇒ 3t = 95 + 2×25 = 145

⇒ t = 48.33

Hence, the final temperature of the mixture = 48.33° C.

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I believe the evidence for this theory is that:

The orbits surrounding Jupiter are highly elliptical which are off the plane of the ecliptic, and many of these moons are retrograde. This is very unlikely for moons or satellites which are formed during the planetary accretion. Hence comes the theory.

Answer:

Whether or not you actually exercise each week is greatly influence by your mindset.

Explanation:

Mindset refers to the way you organize your thoughts and decide to face everyday situations. The way you reflect on a particular situation, and especially how you choose to act upon that personal analysis, can determine your success or failure. So if you can work out each week without fail, it is a big influence by your mindset.

In the event of a boat motor catching fire, prioritize personal safety by ensuring lifejackets are worn, cut off the fuel source if possible, and use a fire extinguisher at the fire's base. If necessary, evacuate the boat.

The immediate actions if a boat motor catches fire should be focused on ensuring personal safety and then attempting to extinguish the fire. Firstly, ensure everyone on board is wearing a lifejacket for safety. Secondly, turn off the fuel source if possible to prevent the fire from spreading. Following this, use a fire extinguisher if one is available, aiming it at the base of the fire. Be cautious and prioritize evacuating the boat if the fire becomes uncontrollable.

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Final answer:

The distance below the top of the well is 806.4 meters. When taking into account the time for sound to travel up the well, the distance is 0 meters.

Explanation:

(a) To calculate the distance to the water, we can use the formula:

Distance = Speed of Sound x Time

Distance = 336 m/s x 2.40 s

Distance = 806.4 m

(b) To calculate the distance taking into account the time for sound to travel up the well, we subtract the time for sound to travel up:

Distance = (Speed of Sound x Time) - Speed of Sound x Time for Sound to Travel Up

Distance = 336 m/s x 2.40 s - 336 m/s x 2.40 s

Distance = 0 m

The threshold frequency fo of Cesium is about 9.39 × 10¹⁴ Hz

[tex]\texttt{ }[/tex]

The term of package of electromagnetic wave radiation energy was first introduced by Max Planck. He termed it with photons with the magnitude is:

[tex]\large {\boxed {E = h \times f}}[/tex]

E = Energi of A Photon ( Joule )

h = Planck's Constant ( 6.63 × 10⁻³⁴ Js )

f = Frequency of Eletromagnetic Wave ( Hz )

[tex]\texttt{ }[/tex]

The photoelectric effect is an effect in which electrons are released from the metal surface when illuminated by electromagnetic waves with large enough of radiation energy.

[tex]\large {\boxed {E = \frac{1}{2}mv^2 + \Phi}}[/tex]

[tex]\large {\boxed {E = qV + \Phi}}[/tex]

E = Energi of A Photon ( Joule )

m = Mass of an Electron ( kg )

v = Electron Release Speed ( m/s )

Ф = Work Function of Metal ( Joule )

q = Charge of an Electron ( Coulomb )

V = Stopping Potential ( Volt )

Let us now tackle the problem!

[tex]\texttt{ }[/tex]

Complete Question:

What is the threshold frequency fo of Cesium?

Note that 1 eV (electron volt) = 1.60×10⁻¹⁹ J ?

[tex]\begin{tabular} {|c|c|c|}\underline{Light\ Energy\ (eV)}& \underline{Electron\ Emitted} & \underline{Electron KE\ (eV)}\\3.87 & no & -\\3.88 & no & -\\ \boxed{3.89} & yes & 0\\3.90 & yes & 0.01\\3.91 & yes & 0.02\end{tabular}[/tex]

Given:

the work function = Φ = 3.89 eV

Asked:

threshold frequency = fo = ?

Solution:

Firstly, we will convert the work function unit as follows:

Φ = 3.89 eV = 3.89 × 1.60 × 10⁻¹⁹ Joule = 6.224 × 10⁻¹⁹ Joule

[tex]\texttt{ }[/tex]

Next, we will calculate the threshold frequensy as follows:

[tex]\Phi = h \times fo[/tex]

[tex]6.224 \times 10^{-19} = 6.63 \times 10^{-34} \times fo[/tex]

[tex]fo = ( 6.224 \times 10^{-19} ) \div ( 6.63 \times 10^{-34} )[/tex]

[tex]{\boxed{fo \approx 9.39 \times 10^{14} ~ Hz}[/tex]

[tex]\texttt{ }[/tex]

[tex]\texttt{ }[/tex]

Grade: High School

Subject: Physics

Chapter: Quantum Physics

Low sun angles spread sunlight over a larger area and through more of Earth's atmosphere, reducing its intensity. The Rosetta spacecraft observed this effect, receiving only 4% of the sunlight intensity experienced on Earth. Other phenomena, like solar activity and volcanic activity, can also impact solar energy on Earth's surface.

Low sun angles result in reduced solar energy due to a fundamental physics principle: the intensity of sunlight is spread over a larger area when it strikes the Earth at a more oblique angle. This occurs, for example, during winter when the Sun is low in the sky. As depicted in Figure 4.6, the Sun's rays spread out over a much wider area, becoming less effective at heating the ground. Moreover, when the sun is low in the sky, the sunlight must travel through more of the Earth's atmosphere, which can scatter the light, reducing the intensity of the sunlight that reaches the ground.

Another point to consider is the observed phenomenon reported by the Rosetta spacecraft at 800 million kilometres from the sun. Rosetta’s solar cells had to be specifically designed to function in these cold, low-light conditions as it receives only 4 percent of the light strength received on Earth.

However, while this explains the reduction in the intensity of solar energy at low angles, it's important to note that other phenomena, such as solar activity and volcanic aerosols, can also affect the global temperatures and solar energy received on Earth's surface.

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Only the vertical height of the stairs is used to calculate work related to gravitational potential energy because work done by gravity is only dependent on vertical displacement. The formula W = mgh is used, where h is the vertical height, which directly increases the gravitational potential energy when climbing stairs.

The reason why only the vertical height of the stairs is measured when calculating work related to an increase in gravitational potential energy (GPE) is that work done by gravity depends only on the vertical displacement in the gravitational field. In the context of climbing stairs, the person does work against the gravitational force to increase their GPE, which is calculated as mgh, where m is mass, g is the acceleration due to gravity, and h is the vertical height. The work going into mechanical energy is given by W = KE + PE. Initially, at the bottom of the stairs, both kinetic energy (KE) and GPE are zero. As a person climbs the stairs, the GPE increases while KE remains unchanged if they climb at a constant speed, making the GPE the significant term in the work-energy equation (W = mgh). We can then calculate work and divide it by time to determine the power output.

The longest wavelength of light in the visible spectrum has the color Red, while the shortest wavelength of light in the visible spectrum has the color Violet.

Electromagnetic spectrum is nothing but the range of wavelengths or frequencies on which electromagnetic radiation extend. it is whole distribution of electromagnetic waves according to frequency or wavelength. Electromagnetic wave is nothing but a photon which carries energy. Photon has frequency, wavelength as well as amplitude. Electromagnetic spectrum is show in figure.

Range from 4000 angstrom to 7000 angstrom from violet to red respectively shows the visible light. Infrared light is nothing but the heat we feel from the sun. and ultraviolet light is blacked by ozone layer. we can calculate exact value of temperature of the sun rom Stephan's forth power law.

Hence longest wavelength is red and shortest wavelength is violet in the visible spectrum of electromagnetic wave.  

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Answer:

Sample Response: No, the resulting wave in the diagram does not demonstrate destructive interference. The resulting wave in the diagram shows a bigger wave than Wave 1 or Wave 2. If it demonstrated destructive interference, it would be a smaller wave or a horizontal line. With destructive interference, waves break down to form a smaller wave, or cancel each other out, resulting in no wave formation.