What are examples of convection currents?

The movement of warm air into cooler air and cooler air into warm air.
The movement of cool water into warmer water and warmer water into the cool water.
The displacement of air/water molecules by other air/water molecules due to varying temperatures.
All of the above.

Answer:

See Explanation

Explanation:

The principle of conservation of energy states that; energy can neither be created nor destroyed but is converted from one form to another.

In view of this principle, Ella can not be correct when she says that a lot of energy has disappeared. The use of the term "disappeared" connotes the idea that the energy no longer exists which does not happen.

Hence, energy can not "disappear" from hot water rather the energy in the water may be transferred to the surroundings.

To answer this question, you need to understand the law of conservation of energy. Essentially, the law states that energy cannot be created or destroyed; it is always conserved.

Knowing this law, how can we answer this question? Well, let's look at what the question tells us. We know that Blackie was initially at the top of a refrigerator before rolling over and falling to the ground. At ground level, he only has Kinetic energy when he lands. Since we know that he started at the top of the fridge, we know that Blackie started off with potential gravitational energy.

That would make sense, right? Written out as an equation, it'd be:

[tex]U_{g}[/tex] = [tex]K_{E}[/tex]

This follows the law of conservation of energy, as all the potential gravitational energy is converted into Kinetic energy.

Now, we know what energies are converted. What can we do with it? Recall the equation of potential gravitational energy:

[tex]U_{g}[/tex] = [tex]F_{g}[/tex]∆H

[tex]U_{g}[/tex] = mg∆H

Do you see it now? ∆H is the distance that Blackie falls, and since Blackie jumps from the fridge to the ground, ∆H must be the height of the fridge!

Let's start solving for ∆H:

[tex]U_{g}[/tex] = [tex]K_{E}[/tex]

Substitute potential gravitational energy with our equation:

mg∆H = [tex]K_{E}[/tex]

We were given the value of Kinetic Energy:

mg∆H = 90

Isolate ∆H by dividing both sides by mg:

∆H = [tex]\frac{90}{mg}[/tex]

Input values for 'm' and 'g' (m is the mass of Blackie and g is Earth's acceleration)

∆H = [tex]\frac{90}{6*9.80}[/tex]

∆H = [tex]\frac{90}{58.8}[/tex]

∆H = 1.53

The refrigerator is 1.53 meters tall.

And that's it! Let me know if you need me to explain anything I did here.

- breezyツ

Answer:

A

Explanation:

Answer:

The force that happens between two particles with mass

Acceleration = (change in velocity) / (time for the change)

Change in velocity = 59.43 m/s East

Time for the change = 0.312 s

Acceleration = 190.5 m/s^2 East

Answer:

D

Explanation:

120/2= 60km per hour

Answer:

4

Explanation:

because they show the direction where that particular object is going and forces are vectors they have both magnitude and direction

Answer:

B

Explanation:

Answer:

The main function of the circulatory system is to carry nutrients to cells and waste away from cells.

Explanation:

Answer:

When a magnet causes a paper clip to move, it's an example of Potential energy being changed in to Kinetic energy

A child running is an example of Kinetic energy

A motionless iron object in the magnetic field of a magnet may be said to have Potential energy

Answer:

The small car and the truck experience the same average force.

Explanation:

Here we need to remember two of Newton's laws.

The second one says that:

F = m*a

force equals mass times acceleration.

And the third one says that;

"If an object A exerts a force on object B, then object B must exert a force of equal magnitude and opposite direction back on object A"

From the third law, if the car experiences a force F due to the impact with the truck, then the truck experiences the same force F due to the impact.

But this seems odd, because we would expect to see the car being more affected by the impact, right?

Well, this is explained by the second law.

Suppose that the mass of the car is m, and the mass of the truck is M.

such that M > m

Then for the small car we have:

F = m*a

And for the truck:

F = M*a'

Because the force is the same for both of them, we can write:

m*a = M*a'

a = (M/m)*a'

because M > m, then M/m > 1.

This means that the acceleration that the car experiences is larger than the acceleration for the truck, and this is why we would see that the car seems more affected by the impact, regardless of the fact that both vehicles experience the same force in the impact.

Answer:

0.075 km/min

Explanation:

[tex]\frac{5km - 0km}{67 min - 0min} = 0.075 km/min[/tex]

Answer:

Correct 40 m/s

Explanation:

Answer: San diego

Because it is closer to the ocean

Answer:

I don't know if I can help you with that

Answer:

temperature is the average kinetic energy of the particles of matter. the hotter something is the more kinetic energy it has.

Explanation:

Answer: Protons are positively charged particles

Explanation:

Answer:

Its true

Explanation:

La respuesta correcta para esta pregunta abierta es la siguiente.

No incluyes opciones, incisos, o alguna referencia específica para responder esta pregunta.

De ahí que responderemos en términos generales basándonos en nuestro conocimiento previo.

El concepto cosmológico abarca todo lo relativo a la cosmología y, al unir este término con la metafísica sería posible una correcta asociación la cual sería benéfica para ambos campos de conocimiento porque de esta manera se estarían complementando y enriqueciendo el uno al otro.

Cuando la ciencia -en este caso, la cosmología- acepte los conceptos metafísico que no tienen un sustento científico pero que sí contemplan alternativas en el mundo espiritual que son aceptadas por una innumerable cantidad de personas, entonces los expertos podrán plantear nuevas y diferentes posibilidades de entender los fenómenos que al día de hoy, carecen de una convincente explicación.

Tanto la cosmología como la metafísica podrían mostrarse más receptivos a las aportaciones de una y la otra, con objeto de poder aumentar las posibilidades de comprender un fenómeno. No necesariamente debe haber una teoría científica para poder avanzar en el conocimiento de algún tema. De ahí que las aportaciones metafísicas sean válidas como una alternativa de investigación.

Answer:

let current flow be x

Explanation:

than we know potential difference = energy supply / charge then 120 = 10 /x then x=12 therefore pd = 12 v

Answer:

The magnitude of the force is 79.893 N.

Explanation:

The magnitude of the electrostatic force between the two particles is determined by Coloumb's Law, whose formula is:

[tex]F = \frac{\kappa \cdot |q_{A}|\cdot |q_{B}|}{r^{2}}[/tex] (1)

Where:

[tex]\kappa[/tex] - Electrostatic constant, in newtons-square meters per square coulomb.

[tex]q_{A}, q_{B}[/tex] - Electric charges, in coulombs.

[tex]r[/tex] - Distance, in meters.

If we know that [tex]\kappa = 8.988\times 10^{9}\,\frac{N\cdot m^{2}}{C^{2}}[/tex], [tex]q_{A} = +40\times 10^{-6}\, C[/tex], [tex]q_{B} = - 80\times 10^{-6}\, C[/tex] and [tex]r = 0.6\,m[/tex], then the magnitude of the force is:

[tex]F = \frac{\kappa \cdot |q_{A}|\cdot |q_{B}|}{r^{2}}[/tex]

[tex]F = 79.893\,N[/tex]

The magnitude of the force is 79.893 N.

Answer:

P2 = 6.67 atm

Explanation:

Given the following data;

Initial volume = 1 Liters

Initial pressure = 5 atm

Final volume = 0.75 Liters

To find the final pressure P2, we would use Boyles' law.

Boyles states that when the temperature of an ideal gas is kept constant, the pressure of the gas is inversely proportional to the volume occupied by the gas.

Mathematically, Boyles law is given by;

[tex] PV = K[/tex]

[tex] P_{1}V_{1} = P_{2}V_{2} [/tex]

Substituting into the equation, we have;

[tex] 5 * 1 = P_{2} * 0.75 [/tex]

[tex] 5 = 0.75_{2} [/tex]

[tex] P_{2} = \frac {5}{0.75}[/tex]

[tex] P_{2} = 6.67[/tex]

P2 = 6.67 atm

Therefore, the new pressure is 6.67 atm.

Answer:

Explanation:

1.-Energía eléctrica ( electricidad ) proveniente de una fuente AC ( es decir de corriente alterna)

2.-Hay un proveedor de servicios que lleva la energía a las comunidades en general y en particular la lleva hasta mi casa y escuela. Se define como acometida eléctrica, la infraestructura que lleva la energía desde la red de distribución al tablero principal en el abonado. La acometida puede ser aérea o subterránea, y normalmente consta de tres conductores ( de los cuales dos son calibre AWG # 8 ( dos fases ) y uno AWG # 10 ( neutro ). Esta configuración permite tener: 120 y 240 (V) en servicio en la casa y suficiente capacidad para la carga eléctrica de una casa normal

3.-Si, el tipo de corriente. En el caso de una linterna se usan "pilas" o baterías de corriente directa ( que no varia en el tiempo), en la casa la corriente es alterna de 60 ciclos por segundo de frecuencia.

4.-Si el voltaje es menor en una medida importante la ampolleta no alumbra por cuanto si por ejemplo el voltaje nominal ( o de funcionamiento es 120 V y el voltaje suministrado es 50 V ese voltaje será insuficiente para hacer funcionar el circuito). Si el voltaje es mayor dígamos 240 V la ampolleta se quema.

5.-El interruptor nos asegura la maniobra a nuestra voluntad del circuito del cual forma parte. Es decir si tengo un circuito de alumbrado ( 1 bombillo y un interruptor ) ese interruptor me permitirá apagar y encender la luz cuando yo quiera.

Los breaker son "interruptores" son dispositivos de protección para caso de sobrecargas y/o cortocircuitos

Answer:

Insolation

Explanation:

It's actually the process when heat is transferred from the sun to the surface of the earth

Answer:

When a right-handed golfer’s tee shot curves to far to the left, the shot is described as a “hook.” This shot typically occurs when the club head moves across the ball from left to right, imparting side-spin on the ball

Answer:

4400

Explanation:

pe=mgh=55*10*8=4400

Answer:

There are the molecular changes water undergoes