8th grade science help help

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It gets this name because it does not melt into a liquid when heated; instead, it changes directly into a gas (a process known as sublimation).

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Answer:

17.6 m/s²

Explanation:

Given:

[tex]v_{f}[/tex] = 90 m/s (final velocity)

[tex]v_{i}[/tex] = 2 m/s (initial velocity)

Δt = 5s (change in time)

The formula for acceleration is:

[tex]a_{avg}[/tex] = Δv / Δt

We can find Δv by doing

Δv = [tex]v_{f}[/tex] - [tex]v_{i}[/tex]

Replace the values

Δv = 90m/s - 2m/s

Δv= 88m/s

Using the equation from earlier, we can find the acceleration by dividing the average velocity by time.

[tex]a_{avg}[/tex] = Δv / Δt

[tex]a_{avg}[/tex] = [tex]\frac{88m/s}{5/s}[/tex]

acceleration = 17.6 [tex]m/s^{2}[/tex]

Answer air circulating in a hot air balloon

Explanation:

Answer:  An Incident on Route 12 is presented here in a high quality paperback edition. This popular classic work by James H. Schmitz is in the English language, and may not include graphics or images from the original edition.

Explanation: I HOPE THAT HELPED

Answer:

All extended structure compounds form cubes. Sodium and chlorine atoms both have cubical shapes. In the extended structure of NaCI, atoms are arranged in a cubical pattern

Answer:

When the temperature of an object increases, the average kinetic energy of its particles increases. When the average kinetic energy of its particles increases, the object's thermal energy increases. Therefore, the thermal energy of an object increases as its temperature increases.

Explanation:

Answer:

what y'all teachers be on

Answer:

I = 3 Amp

Explanation:

Current in a Conductor

The electric current that moves through a conductor is defined as the charge Q that passes through it per unit time.

[tex]\displaystyle I=\frac{Q}{t}[/tex]

The SI unit for the current is the Ampere. One ampere is the current that flows when one coulomb of charge passes a point in a circuit in one second.

It's known that a charge of Q=15 C passes a point in a circuit in 5 seconds, thus the current is:

[tex]\displaystyle I=\frac{15\ C}{5\ s}[/tex]

I = 3 Amp

The current in the circuit is 3 A.

The current in the circuit can be calculated using the formula below.

Formula:

Where:

From the question,

Given:

Substitute these values into the equation.

Hence, the current in the circuit is 3 A.

Learn more about current here: https://brainly.com/question/1100341

Answer:

food chain is a process of how food is transported to the plant and then to the animal that eats the animal. there are primary, secondary, and tertiary and then decompose.

Explanation:

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Answer:

A hierarchical series of organisms each dependent on the next as a source of food.

Explanation:

Hope this helps!! plz mark brainliest-Lily ^_^ ( food chain also known as the Circle Of Life)

Answer:

1. piece b because it’s particles move faster.

2. the microscopic movement of the electrons creates a macroscopic flow of electricity.

3. gravitational energy attracts; energy stored in a magnetic field attracts or repels.

4. thermal energy will increase for as long as the metal is absorbing heat energy.

5. the thermal energy of the ice has increased more than the thermal energy of the beaker.

6. gravitational potential energy and kinetic energy

7. the gravitational potential energy of the river decreases as it changes to kinetic energy

8. the total energy of the system is conserved.

Explanation:

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For a system that contains a rock falling through the air, the total mechanical energy of the system is conserved.

Learn more about mechanical energy: https://brainly.com/question/15025401

Answer:

1.27seconds

Explanation:

Speed = 324 m/s , Distance = 411.48m

Time = Distance/Speed

Time = 411.48/324 seconds

Time = 1.27seconds ( Ans)

Answer:

Force = 21.85N

Explanation:

Given the following data;

Mass = 2.3kg

Acceleration = 9.5m/s²

To find the force;

Force is given by the multiplication of mass and acceleration.

Mathematically, Force is;

[tex] F = ma[/tex]

Where;

F represents force.

m represents the mass of an object.

a represents acceleration.

Substituting into the equation, we have

Force = 2.3 * 9.5

Force = 21.85N

Therefore, the force applied to the rat is 21.85 Newton.

Answer:

Kinetic energy is the energy due to motion. Potential energy is energy stored in matter. The joule (J) is the SI unit of energy and equals (kg×m2s2) ( kg × m 2 s 2 ) .

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Answer:

full moon is the answer to question

Answer:

9000 J

Explanation:

Answer:

False

Explanation:

I took the K.12 test

Answer:

Person above me is correct, False

Explanation:

I go to K12 too (yes, it is K12)

Answer:

The Potential Energy of the Swing is Changing in to Kinetic Energy when is start moving.

Explanation:

When the Swing is pull at its extreme point then it has maximum potential energy. Because the formula of potential energy is:

             P.E. = (1/2)k*x^2

Here x shows the body displacement from the mean (Equilibrium) position. Since at maximum position the displacement is maximum therefore the P.E. is maximum at the extreme point.

When the Swing is released and start moving from extreme position to mean its P.E. is changing into Kinetic Energy. Because with the movement towards the mean position body acquire more speed and that speed increases its velocity. Since Kinetic Energy is given as:

            K.E. = (1/2) m*v^2

Therefore with the increase in velocity kinetic energy increases.

But when body again moving towards the extreme position, its kinetic energy again changes into P.E with the same reason as I discussed in the above paragraph.

Some of the energy is also changes in to heat in order to overcome air resistance.

Answer:

False.

Explanation:

Human diversity means differences among people. Therefore, it's each of us in our rich and infinite indistinguishable features; this is basically the fundamental building block of culture. For example, a doctor might enjoy watching football and educational documentary programs while another enjoys listening to music and watching thriller movies.

Culture can be defined as the general way of life of a group of people living together in a particular location or society.

Basically, culture comprises of beliefs, values, behaviors, language, dressing, cuisine, music, symbols, arts, social habits, knowledge, customs, laws pertaining to a particular group of people living together in a society.

This ultimately implies that, culture are acquired and passed from one generation to another.

A cultural trait can be defined as the smallest characteristics of human activity (actions) that is mainly acquired socially and transmitted from one generation to another through various modes of communication. Thus, these unique behavioral informations or characteristics and beliefs acquired by people socially are transmitted from one individual or group of people to another.

The image that shows an example of the strong nuclear force in action should be considered option d.

The strong nuclear force is known as the  strong force or the strong interaction.

This force is strong when it overcomes the repulsive force that lies between the two positively charged protons where the neutrons and protons should be permitted for sticking together.

Hence, The image that shows an example of the strong nuclear force in action should be considered option d.

Learn more about force here: https://brainly.com/question/24710640

Answer:

466J

Explanation:

Given parameters:

Mass of steel  = 1kg  = 1000g

Initial temperature  = 21°C

Final temperature  = 22°C

Unknown:

Amount of heat required for this temperature increase  = ?

Solution:

To solve this problem, we use the expression below:

  So;

Heat absorbed  = mass x specific heat of steel x change in temperature

Specific heat of steel  = 0.466J/g°C  

Therefore;

 Heat absorbed  = 1000 x 0.466 x (22  - 21)  = 466J

Calculate the velocity(v) at the bottom of hill.

As we know ,

[tex] \bf\: Kinetic \: energy = \dfrac{1}{2} \times m \times {v}^{2} [/tex]

[tex] \red \bigstar \bf \: putting \: the \: values[/tex]

[tex] \rightarrow \: 25 = \dfrac{1}{2} \times 2 \times {v}^{2} [/tex]

[tex] \rightarrow \: 25 \times 2 = 1 \times 2 \times {v}^{2} [/tex]

[tex] \rightarrow \: 50 = 2 \times {v}^{2} [/tex]

[tex] \rightarrow \: {v}^{2} = \cancel \dfrac{50}{2} [/tex]

[tex] \rightarrow \: {v}^{2} = 25[/tex]

[tex] \rightarrow \: v = \sqrt{25} [/tex]

[tex] \rightarrow \: v = 5 \: m {s}^{ - 1} [/tex]

Answer:

B

Explanation:

Answer:

Force

Motion

position

Explanation:

Deanna's niece loves to swing at the local playground, so Deanna takes her and pushes her on the swing. Deanna must use force to exert a motion that causes the swing to change position.

Answer:

v = 2 m/s

Explanation:

First, we find the angular velocity of the girl by using the following formula:

[tex]Angular\ Velocity =\omega= \frac{Angular\ Distance\ Covered}{Time\ Taken}\\\\\omega = \frac{1\ revolution}{10\ min}\frac{1\ min}{60\ s}\frac{2\pi\ rad}{1\ revolution}\\\\\omega = 0.01\ rad/s[/tex]

Now, for the average velocity of the girl we can use the following formula:

[tex]Average\ Velocity = V = r\omega\\V = (200\ m)(0.01\ rad/s)\\[/tex]

where,

r = radius = 200 m

therefore,

v = 2 m/s

Answer:

15m

Explanation:

change in real depth = 80 - 60 = 20m

Let us assume that the index is 4/3

Refractive index = change in real depth ÷ change in apparent depth

change in apparent depth = change in real depth÷ refractive index

= 20÷(4/3) = 20×(3/4) = 5×3 = 15m

Answer:

250 m/s

Explanation:

Answer:

250m/s

Explanation:

Frequency = velocity/wavelength

Then rearrange,

Velocity = frequency x wavelength

Velocity = 500 x 9.5 = 250m/s