According to Einstein's famous formula, the relationship between mass and energy can be written E = M ∙ c2, where E = energy in joules, m = mass in kilograms and c = speed of light in meters per second. Sweden's annual energy use amounts to approximately 1.35 ∙ 10 up tp 18J. Suppose that all this energy could be created by converting matter into energy. If so, how much mass would be needed to cover the country's annual energy use?
The speed of light is 3 ∙ 10 up to 8 m / s

Answer:

156.8 Joules

Explanation:

Work = Force x Displacement

Displacement = 2m

Force (force of gravity) = mass x acceleration due to gravity =  8Kg x 9.8m/s^2

= 78.4N

Work = FxD

Work = 78.4 N x 2m

Work = 156.8 N·m  OR 156.8 Joules

The amount of work done in lifting this box is equal to 156.8 Joules.

Given the following data:

Scientific data:

To calculate the amount of work that is done in lifting this box:

Mathematically, the work done by a person is calculated by using this formula:

[tex]Work\;done = Fd = mgd[/tex]

Where:

Substituting the given parameters into the formula, we have;

[tex]Work\;done = 8 \times 9.8 \times 2[/tex]

Work done = 156.8 Joules.

Read more on work done here: https://brainly.com/question/25573309

Answer:

B. 90km/hr

Explanation:

The formula for finding velocity =

Displacement/time

The displacement of the car has been given to be = 1215 km West

Time it took to go from Dallas to Paso = 13.5 hours

Then velocity = 1215/13.5

= 90

Therefore velocity = 90km/hour

Option B is the correct answer to this question.

Thank you!

Answer:

E = 50850[kJ]

Explanation:

To boil the water we must use the latent heat of vaporization. Also we need to multiply this value by the mass of the water.

[tex]E=m*H_{v}[/tex]

Where:

E = energy produced by heat [J]

m = mass = 225 [kg]

Hv = 226000 [J/kg]

[tex]E = 225*226000\\E = 50850000 [J]\\E=50850[kJ][/tex]

Answer:

1m/s²

Explanation:

Given parameters:

Initial velocity  = 2m/s

Final velocity  = 4m/s

Time of chase  = 2s

Unknown:

Acceleration = ?

Solution:

Acceleration is the rate of change of velocity with time;

 A = [tex]\frac{v - u }{t}[/tex]  

A is the acceleration

v is the final velocity

u is the initial velocity

t is the time taken

      A  = [tex]\frac{4 - 2}{2}[/tex]   = 1m/s²

Answer:

A convex lens or converging lens focuses the light rays to a specific point whereas a concave lens or diverging lens diverges the light rays. When these lenses are combined, they produce sharper images. Most of the eyeglass lenses use combinations of convex and concave lenses.

Answer:

4km/hr

Explanation:

The projectile is any object thrown into space upon which the only acting force is gravity. In other words, the primary force acting on a projectile is gravity. This doesn’t necessarily mean that the other forces do not act on it, just that their effect is minimal compared to gravity. The path followed by a projectile is known as a trajectory. A baseball batted or thrown and the instant the bullet exits the barrel of a gun are all examples of the projectile.

When a particle is thrown obliquely near the earth’s surface, it moves along a curved path under constant acceleration that is directed towards the center of the earth (we assume that the particle remains close to the surface of the earth). The path of such a particle is called a projectile and the motion is called projectile motion. Air resistance to the motion of the body is to be assumed absent in projectile motion.

In a Projectile Motion, there are two simultaneous independent rectilinear motions:

Along the x-axis: uniform velocity, responsible for the horizontal (forward) motion of the particle.

Along y-axis: uniform acceleration, responsible for the vertical (downwards) motion of the particle.

Accelerations in the horizontal projectile motion and vertical projectile motion of a particle: When a particle is projected in the air with some speed, the only force acting on it during its time in the air is the acceleration due to gravity (g). This acceleration acts vertically downward. There is no acceleration in the horizontal direction, which means that the velocity of the particle in the horizontal direction remains constant.

[tex]\sf~~~~~~~~~~~~~~~{\red{\underbrace{\underline{\green{projectile~motion}}}}}[/tex]

Projectile motion is a form of motion in which object or particle is thrown near earth's surface and it moves along a curved path under the action of gravity only.

Explanation:

W=f×d

=20×6

w=120 joule

Answer:

Answer:

These atomos are called isotopes.

Explanation:

Each chemical element is characterized by the number of protons in its nucleus, which is called the atomic number (Z).

The number of neutrons in the nucleus can vary. There are almost always as many or more neutrons than protons. The atomic mass (A) is obtained by adding the number of protons and neutrons in a given nucleus.

The same chemical element can be made up of different atoms, that is, their atomic numbers are the same, but the number of neutrons is different. These atoms are called isotopes of the element. That is, isotopes are atoms whose atomic nuclei have the same number of protons but different numbers of neutrons.

So, these atomos are called isotopes.

Explanation:

In Newton's 1 law, an object will not change its motion unless a force acts on it.

The motion of a ball falling down through the atmosphere, or a model rocket being launched up into the atmosphere are both examples of Newton's first law. 

In Newton's 2 law, the force on an object is equal to its mass times its acceleration.

Riding your bicycle is a good example of this law of motion at work. ... Your leg muscles pushing pushing on the pedals of your bicycle is the force. When you push on the pedals, your bicycle accelerates.

In Newton's 3 law, when two objects interact, they apply forces to each other of equal magnitude and opposite direction.

For example, when you jump, your legs apply a force to the ground, and the ground applies and equal and opposite reaction force that propels you into the air.

Answer: B

"Ball 1 at 0.21 m/s left, Ball 2 at 0.22 m/s left"

Complete question:

A train has an initial velocity of 44m/s and an acceleration of -4m/s². calculate its velocity​ after 10s ?

Answer:

the final velocity of the train is 4 m/s.

Explanation:

Given;

initial velocity of the train, u = 44 m/s

acceleration of the train, a = -4m/s² (the negative sign shows that the train is decelerating)

time of motion, t = 10 s

let the final velocity of the train = v

The final velocity of the train is calculated using the following kinematic equation;

v = u + at

v = 44 + (-4 x 10)

v = 44 - 40

v = 4 m/s

Therefore, the final velocity of the train is 4 m/s.

Answer: A negatively-charged ion always has more electrons than protons

Explanation:

First, we know that the elementary negative charge is the electron, while the positive one is the proton. Such that both have the same charge in magnitude, but a different sign. Such that if we have the same number of electrons and protons in an atom, the charge of this atom will be neutral.

And an ion is an atom with a different number of electrons and protons, so the charge of the atom is not neutral.

Then if we have a negatively-charged ion, the charge of this atom is negative. Then we must have a larger number of electrons (the negative ones) than protons (the positive ones)

Then the correct option is:

A negatively-charged ion always has more electrons than protons

Answer:

down below

Explanation:

for a scale, kg is used, as well as grams

for force, newtons is used

Answer:

what's the question?........

Answer:

6m

Explanation:

2+4=6

Answer:

The last option.

Explanation:

Since you are going down, the gravitational potential energy would go down too. Thus, the gravitational potential energy decreases.

Since the gravitational potential energy is converted to kinetic energy when you move down, there is an increase in kinetic energy.

Answer:

The fourth option

Explanation:

Answer:

ball 4 has a positve charge

Explanation:

-Ball 2: is negative because it is repelled by ball one (like signs repel)

- ball 3: is also negative because it is repelled by ball one (like signs repel)

- Ball 4: is positive because it is attracted by ball 3 (opposite signes attract)

Answer:

endoplasmic reticulum

Answer:

The horizontal distance traveled by the skydiver is 510.8 m.

Explanation:

Given;

height of fall, h = 800 m

initial velocity of the airplane, u = 40 m/s

The time to fall to the ground is calculated as;

[tex]t = \sqrt{\frac{2h}{g} } \\\\t = \sqrt{\frac{2 \times 800}{9.81} }\\\\t = 12.77 \ s[/tex]

The horizontal distance or range of the motion is calculated as;

R = ut

R = 40 m/s x 12.77 s

R = 510.8 m

Therefore, the horizontal distance traveled by the skydiver is 510.8 m.

Answer:

For, heating purposes more the quantity of  water more will be the heating. Clearly, underground heating would have more water and hence, it will have edge over the  water heater system.

Moreover, for things at the same temperature, the thing with more molecules has more total kinetic energy (thermal energy) than the thing with fewer molecules. The groundwater heating system uses heat from the heat stored naturally in groundwater or aquifers. Thus, saving the cost of power required to heat in normal water heater.

Explanation:

The groundwater heating system will warm the school more than the water heater system due to the fact that it uses more water more than the other system.

Based on the complete question, it should be noted that the addition of energy leads to an increase in motion which results in the rise in temperature.

The groundwater heating system will warm the school more than the water heater system due to the fact that it uses more water more than the other system even though its water isn't as warm as in the other system.

Read related link on:

https://brainly.com/question/20116115

Answer:

Gravity controls the movement of the planets around the sun, holds together stars grouped in galaxies, and galaxies grouped in clusters.  The Universal Law of Gravitation depends on two things.  First it depends on mass of each object  and the second factor is the distance between two objects.  If the mass of one object is Larger, the gravitational pull towards it will be larger  and the smaller distance, the larger the gravitational pull will be between the objects. Therefore the Larger planets have more moon and the inner planets have less.

Explanation:

Answer:

6 protons

Explanation:

Answer:

When the  water is frozen it turns to ice and the density decreases.

Explanation:

Have A Wonderful Day !!

Answer:

Fscos63

Explanation:

Given that a horizontal pole is attached to the side of a building. There is a pivot P at the wall and a chain is connected from the end of the pole to a point higher up the wall. There is a tension force F in the chain. What is the moment of the force F about the pivot P?

Taking the moment from the pivot point P, that means the moment at point p = 0

Then, if we consider the weight mg of the pole, according to the principle of equilibrium : sum of the upward forces equal to the sum of the downward forces.

Therefore, mg = Fsinø ....... (1)

Also, taking moment at point P

Let the length of the pole = s

The length of the weight of the pole = 1/2 S

Fscosø = mgs/2

The distance s will cancel out

2Fcosø = mg ...... (3)

Substitute mg in equation 1 into equation 3

2fcosø = fsinø

F will cancel out

Tanø = 2

Ø = tan^-1(2)

Ø = 63.4 degree

The moment of force F about pivot point P will be

Moment = force × distance

Moment = Fcos63 × S

Moment = Fscos63

Answer:

Answers below--

Explanation:

1. F/Force

2.H/Contact force

3.A/Non-contact force

4.C/electric force

5.D/gravity

6.I(i)/magnetic force

7.J/kilogram

8.G/newton

9.B/friction

10.E/lubricant

Answer:

20.3N

Explanation:

Given parameters:

Area of the eardrum  = 0.0002m²

Pressure on the eardrum  = 1atm  = 101325Nm⁻²

Unknown:

Force exerted on the eardrum  = ?

Solution:

Pressure is the force per unit area impacted on a body.

      Pressure  = [tex]\frac{Force }{area}[/tex]  

  Force  = Pressure x  area

Now insert the parameters and solve;

  Force  =  101325Nm⁻²  x  0.0002m²  = 20.3N

Answer:

Mass = 18.0 kg

Explanation:

From Hooke's law,

F = ke

where: F is the force, k is the spring constant and e is the extension.

But, F = mg

So that,

mg = ke

On the Earth, let the gravitational force be 10 m/[tex]s^{2}[/tex].

3.0 x 10 = k x 5.0

30 = 5k

⇒ k = [tex]\frac{30}{5}[/tex] ................ 1

On the Moon, the gravitational force is [tex]\frac{1}{6}[/tex] of that on the Earth.

m x [tex]\frac{10}{6}[/tex] = k x 5.0

[tex]\frac{10m}{6}[/tex] = 5k

⇒ k = [tex]\frac{10m}{30}[/tex] ............. 2

Equating 1 and 2, we have;

[tex]\frac{30}{5}[/tex]  = [tex]\frac{10m}{30}[/tex]

m = [tex]\frac{900}{50}[/tex]

    = 18.0

m = 18.0 kg

The mass required to produce the same extension on the Moon is 18 kg.

Answer:

18 kg

Explanation:

On Earth, acceleration of gravity is 10 m/s²

Since weight is a force, the force is 30 N. The value of spring constant is unknown

Spring constant is 6. Now let's find the mass on the Moon

Gravitational acceleration of the moon is 1/6 of that on Earth. Earth's g = 10, so Moon's g = 10/6

The mass is 18 kg