Answer:
net force= -50N +70N
=20N
Explanation:
The balls are moving in opposite directions as indicated and to the right is (-) while to left is (+). Therefore net force is equal to sum of the force
The cue ball travels to the left with a force of +70 N and collides with the four-ball moving towards the right with a force of -50 N.
What is Force?A push or a pull that alters or tends to alter an object's uniform motion or state of rest, as well as altering an object's direction or shape, is referred to as force. It either accelerates items or increases the pressure they are under. The interaction between two items is, to put it simply, a push or a pull on the object. It is the fundamental driver of motion starting from stillness.
Given information according to the question,
The cue ball travels to the left with a force of +70 N and,
The force by four balls moving to the right is -50 N.
Net force, N = 70 N - 50 N
N = 20 N towards the left direction.
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as a ferromagnetic object gets closer to the magnet, the magnetic force pulling the object decreases exponentially.
Ferromagnetic substance are strongly attractive to a magnet.
Ferromagnetic material are those materials which shows magnetic property also in the absence of external magnetic field
It's Atom have permanent dipole moment present in domains.
These are used in the industry.
example of ferromagnetic substance are nickel, iron ,Cobalt etc
When ferromagnetic object is placed in a magnetic field the domains will oriented in the direction of magnetic field even after the removal of applied magnetic field it will not change the shows that it become a permanent magnet.
Magnetic force on ferromagnetic object depends on the strength of the object and also size of the object
The given question is incomplete. The complete question is.
as a ferromagnetic object gets closer to the magnet, the magnetic force pulling the object decreases exponentially
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what is the major cause of the earth’s magnetic field? the earth’s liquid outer core the earth’s liquid outer core the earth’s magnetic lithosphere the earth’s magnetic lithosphere charged particles from the sun charged particles from the sun magnetic materials on the earth’s surface
The earth's liquid outer core is the major cause of the earth’s magnetic field.
What is magnetic field?The magnetic influence on moving electric charges, electric currents, and magnetic materials is described by a magnetic field, a vector field. A force acting on a charge while it travels through a magnetic field is perpendicular to both the charge's motion and the magnetic field. The magnetic field of a permanent magnet attracts or repels other magnets as well as ferromagnetic elements like iron. A magnetic field that varies with location will also exert a force on a variety of non-magnetic materials by changing the velocity of those particles' outer electrons. Electric currents, like those utilised in electromagnets, and electric fields that change over time produce magnetic fields that surround magnetised things.
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to determine your line of , you would need to know the angle your location (line) makes with the equatorial plane at earth's center.
To determine your line of latitude , you would need to know the angle your location (line) makes with the equatorial plane at earth's center.
What is Line of latitude?This is also referred to as parallels and it is defined as the imaginary lines that divide the Earth. They run from east to west and are used to specify the north and south sides of the Earth.
To determine the line of latitude , it is imperative to know the angle your location (line) makes with the equatorial plane at earth's center which is therefore the reason why it was chosen as the most appropriate choice.
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Imagine that the entire Sun, of mass MS , collapses to a sphere of radius Rg such that the work required to remove a small mass m from the surface would be equal to its rest energy mc² . This radius is called the gravitational radius for the Sun.
(b) Find a numerical value for Rg .
The value of radius (Rg) is 1.475km .
Given,
The mass of the sun = Ms
Radius of the sphere = Rg
work required to remove a small mass (m) from the surface would be equal to its rest energy mc^2 .
The given radius (Rg) is called the gravitational radius for the sun.
We know,
Gravitational potential energy or work done
= Ug = GMs×m/Rg
the given rest energy = E =mc^2
As, it is given that the required work or energy is equal to rest energy,
thus, Ug=E
GMs×m/Rg = mc^2
Rg = GMs/c^2
We know,
G = 6.67×10^-11 N. m^2/kg^2
Ms = 1.99×10^30 kg
c = 3×10^8 m/s
Thus, Rg = 6.67×10^-11 × 1.99×10^30 / (3×10^8)^2
Rg = (13.2733×10^19)/(9×10^16 )
Rg = 1.4748×10^3 m
Rg = 1.475km
Hence, The value of radius (Rg) is 1.475km .
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A cubical surface surrounds a point charge q . Describe what happens to the total flux through the surface if (e) the charge is moved outside the surface.
Gauss law explains that the electric flux is defined as the electric field multiplied by the area of the surface in a plane perpendicular to the field.
Mathematically,
Φ=Q ϵo
Where;
Q is enclosed charge
ϵo is the permittivity of the free space
In the case where the charge is moved outside the surface, the flux in the electric field becomes zero because the enclosed charge becomes zero. Thus, the electric field will change due to the movement outside the surface. The only instances where flux is kept constant are when it is moved within the surface or the enclosing object is changed.
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A bicyclist traveling at 5 m/s hits a fence, the bicyclist files over the fence. Which
of Newton's Laws does this BEST describe?
1.Newton’s 1st Law
2.Newton's 2nd Law
3.Newton's 3rd Law
The Newton's Laws that BEST describe the situation is Newton's second law of motion.
What is Newton's second law of motion?
Newton's second law of motion states, the force exerted by an object is directly proportional to the product of mass and acceleration of the object.
Also, the law can also be states as force is equal to the rate of change of momentum.
F ∝ Δp
Ft = m(v2 - v1)
The force exerted on the bicyclist by the fence is equal to the change in momentum of the bicyclist. The bicyclist was able to fly over the fence because there is a change in his momentum.
Thus, the Newton's Laws that BEST describe the situation is Newton's second law of motion.
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Consider cyclic processes completely characterized by each of the following net energy inputs and outputs. In each case, the energy transfers listed are the only ones occurring. Classify each process as (a) possible, (b) impossible according to the first law of thermodynamics, (c) impossible according to the second law of thermodynamics, or (d) impossible according to both the first and second laws.(vi) Input is 5J of energy transferred by heat, and output is 3J of work plus 2J of energy transferred b
The situation is possible based on the first law of thermodynamics.
What is thermodynamics?The term thermodynamics has to do with the study of heat. Heat is that which causes the temperature of a body to change. We know that according to the first law of thermodynamics, energy could neither be created nor destroyed but can be converted from one form to another.
The second law of thermodynamics states that, the conversion of energy is not 100% efficient as some of the energy could be lost as heat. We can now fit in the scenario described into the laws of thermodynamics.
We can see that, if we input is 5J of energy transferred by heat, and output is 3J of work plus 2J of energy transferred by heat, then the situation is possible based on the first law of thermodynamics.
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Q|C A bat, moving at 5.00 m/s , is chasing a flying insect. If the bat emits a 40.0 -kHz chirp and receives back an echo at 40.4 kHz , (a) what is the speed of the insect?
The speed of the insect is 3.03m/s.
What is speed?The speed of an object, also known as v in kinematics, is a scalar quantity that refers to the size of the change in that object's position over time or the size of the change in that object's position per unit of time. The instantaneous speed is the upper limit of the average speed as the duration of the time interval gets closer to zero. The average speed of an object over a period of time is calculated by dividing its distance traveled by the length of the interval. Distance divided by time is the dimension of speed.
Explanation:
The frequency that is received by the source after the reflection is given by,
[tex]f_{1} =f_{0} (\frac{V-v}{V-V_{b} } )(\frac{V+v_{b} }{V+v} )[/tex]
[tex]40.4=40 (\frac{343-v}{343-5} ) x (\frac{343+5}{343+v} )\\[/tex]
[tex]v=3.03 m/s[/tex]
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What creates a magnetic field? More than one answer may be correct. (a) a stationary object with electric charge (b) a moving object with electric charge (c) a stationary conductor carrying electric current (d) a difference in electric potential (e) a charged capacitor disconnected from a battery and at rest Note: In Chapter 34, we will see that a changing electric field also creates a magnetic field
Electricity can be applied to a wire to produce a magnetic field. Charged particles that are in motion produce all magnetic fields. Due to the continually moving electrons inside, even the magnet on your refrigerator is magnetic.
Describe the magnetic field?Magnetic forces can be observed in a magnetic field, an electric current, a changing electric field, or a vector field around a magnet. Magnetic compass needles and other permanent magnets line in the direction of magnetic fields similar to those found on Earth. Electrically charged particles are forced to move in a circular or helical path via magnetic fields. The operation of electric motors is generated by this force, which is applied to electric currents in wires in a magnetic field.
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A ray of light is incident at an angle of 30° on the angle through which the ray is minimally a glass prism of refractive index 1.5. Calculate deviated in the prism. (The medium surrounding the prism is air)
Typically, the "refracted angle" is used to refer to the "angle of deviation."
Snell's Law is simply applied in this case.
Since n1sin1 = n2sin2,
The incidence angle is 1
The refracted angle is 2
The appropriate indices of refraction are n1 and n2.
the standard value for air, n1, is 1.
n2 = 1.5
What is the first rule of Snell?As a result, the refractive indices of the two media may be related through the angle associated with incidence and refraction. The incident ray, the refracted ray, and the normal ray are all said to be on the same plane.
Snell's Law is particularly significant for optical technologies like fibre optics. According to Snell's Law, the refractive indices of the materials at the contact are proportional to the ratio of the sine of the angles of incidence and transmission.
The extension is obeyed by the e-ray Because the refractive index of an e-ray changes with the angle between the wave vector and optical axis, Snell's law applies. It is important to consider e-ray propagation in the uniaxial crystal.
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Brainliest Given:
Reflection is when a wave hits a surface and bounces off of it. Light can bounce off of a mirror so you can see yourself, and sound can bounce off of a wall so you hear an echo.
Refraction is when waves bend when they go into a different substance. This makes objects underwater look like they’re in a different spot than they actually are, and can make your straw look ‘crooked’ in your glass.
Diffraction is when waves bend as they go through openings, and around corners or objects. Sound diffracts more than light does, so it is easy to hear things around corners but impossible to see them.
Interference happens when the crests of two waves meet and build a bigger one, or a crest and trough come together and make a smaller one. This can make sound louder or softer, and light brighter or dimmer.
Decide which type of wave interaction is described below:
1. You can see the mountain peaks on the surface of a lake.
2. You try and spear a fish in a pond, but it hits just next to it.
3. You can still hear a concert even though you are in the parking lot.
4. Students are talking normally in the cafeteria, but it sounds very loud in there.
5. A big wave in a pool hits another wave, and it becomes mostly flat.
6. You use your window as a mirror.
7. Part of your fishing pole drops in the water, and it looks like it broke.
8. You hear a car in the driveway, even though you are on the other side of the house.
Answer: 1. Reflection
2. Refraction
3.Diffraction
4. Diffration
5.Interference
6. Reflection
7. Refraction
8. Diffraction
Good luck !
A small car weighs 10168.25 N. What is its mass?
Answer:
1036.5kg
...................
A 25 kg block is pulled with an applied force of 200 N across a horizontal surface. The block experiences a frictional force of 75 N.a. Draw a free-body diagram for the block, including all forces acting on the block.
b. Determine the net force acting on the block.
c. Calculate the acceleration of the block.
Answer:
see attachment for the answer.
Explanation:
Three solid plastic cylinders all have radius 2.50cm and length 6.00cm. Find the charge of each cylinder given the following additional information about each one. Cylinder (a) carries charge with uniform density 15.0 nC/m² everywhere on its surface. Cylinder
By the charge density, the surface area of the cylinder charge is 0.20 nC.
We need to know about charge density to solve this problem. The charge density can be determined as
λ = Q / A
where λ is charge density, Q is charge and A is surface area.
The parameter given is the charge density and the solid cylinder shape which are :
λ = 15 nC/m²
r = 2.5 cm = 0.025 m
L = 6.0 cm = 0.06 m
Find the surface area of cylinder
A = 2πrL + 2πr²
A = 2π. 0.025. 0.06 + 2 . π . 0.025²
A = 0.0134 m²
Find the charges
Q = λ x A
Q = 15 x 0.0134
Q = 0.20 nC
Hence, the surface area of the cylinder charge is 0.20 nC.
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A nonconducting ring of radius 10.0 cm is uniformly charged with a total positive charge 10.0μC. The ring rotates at a constant angular speed 20.0 rad/ s about an axis through its center, perpendicular to the plane of the ring. What is the magnitude of the magnetic field on the axis of the ring 5.00 cm from its center?
The magnitude of the magnetic field on the axis of the ring 5 cm from its center is 143 pT.
The radius of the nonconducting ring is R = 10 cm.
The ring is uniformly charged q = 10 μC.
The angular speed of the ring, ω = 20 rad/s
The ring is x = 5 cm from the center of the ring.
Now,
R = 10 cm = 0.1 m
q = 10.0 μC = 10 × 10⁻⁶ C
x = 5 cm = 0.05 m
The magnetic field on the axis of a current loop is given as:
[tex]B =\frac{\mu_{0}IR^{2}}{4 \pi(x^{2}+R^{2})^{\frac{3}{2} }}[/tex]
Now, [tex]I = \frac{q}{\frac{2 \pi}{\omega} }[/tex]
So, the magnitude of the magnetic field which is directed away from the center is:
[tex]B =\frac{\mu_{0} \omega qR^{2}}{4 \pi(x^{2}+R^{2})^{\frac{3}{2} }}[/tex]
[tex]B = \frac{\mu_{0} \times(200) \times (10 \times 10^{-6}) \times (0.1)^{2}}{4 \pi((0.05)^{2}+(0.1)^{2})^\frac{3}{2} }[/tex]
B = 1.43 × 10⁻¹⁰ T
B = 143 pT
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an iron bolt of mass 72.0 g hangs from a string 38.8 cm long. the top end of the string is fixed. without touching it, a magnet attracts the bolt so that it remains stationary, but is displaced horizontally 27.0 cm to the right from the previously vertical line of the string.
The weight of the iron bolt is 0.706N
What do you mean by the vertical line of the string?A line that is perpendicular to the surface or another line that is regarded as the base is the vertical line. In coordinate geometry, the vertical lines are often perpendicular to the horizontal lines and parallel to the y-axis. Any straight line that runs from top to bottom or bottom to top is considered to be a vertical line. Standing lines are another name for vertical lines. The vertical lines that we typically draw connect the bases of a square or a rectangle. We shall examine the idea of the vertical line and its characteristics in this essay.
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Why does hitting a magnet with a hammer cause the magnetism to be reduced?
Hitting a magnet with a hammer cause the magnetism to be Physical disruption and vibration damage the material's order, demagnetizing it.
Explanation:There are numerous methods for demagnetizing a magnet.
A magnet, as we know, has magnetic moments, which are the arrangements of molecules in a specific direction.
The hammer causes the magnetic poles of the magnet to point in opposite directions, causing the magnet to bend.
When we repeatedly hammer on a magnet, the magnetic dipoles inside the magnet are released from their ordered configuration.
Magnetism is known to be caused by the presence of magnetic moments.
As a result, when we hammer it, the dipoles are perturbed, lose their orientation, and magnetic moments cease to exist. As a result, the magnet will become demagnetized.
What is Magnetism?The force that magnets use to either attract or repel one another is known as magnetism.
Electric charges in motion are what generate magnetism. Every substance is made of small particles known as atoms.
Electrons, which are charged particles, are found in every atom. Electrons spin like tops around an atom's nucleus, or center. Their mobility causes an electric current to flow, causing each electron to act as a miniature magnet.
Another strongly magnetic substance must enter the magnetic field of an existing magnet in order to be magnetized. A magnet's magnetic field is the area of magnetic force that surrounds it.
An electric current can magnetize some compounds.
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special clothes needed or worn in church
Answer: If you want to know how to dress for church, something modest and comfortable should be fine. Generally, graphic tees that show off sports team logos or bands should never be worn to church. Solid-colored tops are fine, and even something with a pattern should be OK to wear.
Explanation:
Four toy cars are moving at a constant speed until they experience an unbalanced force of 12 n each. Which toy car would have an acceleration of 3 m/s2 ?.
Answer: the car mass with four would have an accelaration
Explanation:
I can’t think of the answer for this question
The car started 15 ml west of Mulberry road.
Consider the East-West route as the x-axis, and place Mulberry Road's intersection at x = 0. This implies that, the west of the intersection is -ve and the east side will be represented positive.
Given the car ends up at 18 mi West to the intersection, implies that it ends at -18mi from x = 0. Also given the total displacement = - 33mi.
Hence, initial position = final position - displacement
= -18 - (- 33)
= -18 + 33
= 15 mi. So, the car started from 15mi from the Mulberry road and from the East of it.
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Find the net electric flux through (c) What can you conclude about the charges, if any, inside the cylindrical surface?
The net flux is positive so the charge in the cylinder is positive To be a uniform field, the field lines mug originate from a plane of charge The net charge inside the cylinder is positive and is distributed on a plane parallel to the ends of the cylinder.
Electric flux, property of an electric field that may be thought of as the number of electric lines of force (or electric field lines) that intersect a given area. Electric field lines are considered to originate on positive electric charges and to terminate on negative charges.
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Suppose you are facing a tall makeup mirror on a vertical wall. Fluorescent tubes framing the mirror carry a clockwise electric current.(i) What is the direction of the magnetic field created by that current at the center of the mirror? (a) left (b) right (c) horizontally toward you (d) horizontally away from you (e) no direction because the field has zero magnitude
The direction of the field the current creates at a point on the wall outside the frame to the right is horizontally towards you.
If the direction of a magnetic field around a vertical electrical wire is counter clockwise, what direction is the electrical current moving?The current will flow from the bottom of the wire to the top if the magnetic field around a vertical electrical wire is counter clockwise in direction. A magnetic field, a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. When a charge moves through a magnetic field, a force that is perpendicular to both its own velocity and the magnetic field operates on it.
A permanent magnet's magnetic field pulls on ferromagnetic materials like iron and draws or repels other magnets. Since the direction and strength of a magnetic field can vary depending on the location, it can be mathematically described by a function that gives each point a vector.
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What is true about the nodes and antinodes of a standing wave? a. they decrease in number with time. b. they remain in a fixed position. c. their position keeps changing with time. d. they increase in number with time.
The nodes and antinodes of a standing wave always remain in a fixed position.
In a standing wave, the nodes and anti-nodes are present at fixed points.
The pattern of a standing wave shows that nodes result from destructive interference and anti-node result form constructive interference.
From a rest position, if we observe nodes and anti-node positions then we can see that nodes have zero displacement while anti-nodes are points that exhibit maximum displacement between two waves.
To put it simply, in Physics, the nodes and anti-nodes are two integral phases of a standing wave.
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Joe walks 36m north followed by 90m east. What is his magnitude of displacement
from the start?
Answer: 90m - 36m = 54 m from the start! Best of luck!
In a transverse wave, the motion of the disturbance is in what direction relative to the wave motion?.
In a transverse wave, the motion of the disturbance is perpendicular to the direction of the wave motion.
A wave is a disturbance that travels through a medium. Depending on the direction of movement of the individual particles relative to the direction of the propagation of the wave, waves can be divided into longitudinal wave and transverse waves.
A transverse wave is a type of wave in which the individual particles of the medium move in a perpendicular direction relative to the direction of wave propagation. This phenomenon can be observed on a water wave. If we place a floatable object on a rippled water surface, it tends to oscillate up and down. This is because the water molecules are also oscillating up and down, perpendicular to the direction of the wave.
Other examples of transverse waves include electromagnetic waves and seismic waves.
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it's possible to transfer electric charge to an object so that its net electric charge is 6.5 times the fundamental electric charge, e.
It's possible to transfer electric charge to an object so that its net electric charge is 6.5 times the fundamental electric charge e. it is a false statement. because any charge can only be integral multiple of the fundamental charge e.
What is electric charge?A neutral body gets charged if it gains or losses some electrons.
There are two types of charges: positive charge and negative charge.
It is the property of substances due to which a body produce and experience electric effect.
S.I. unit of charge is coulomb.
Q = It
Where, Q = charge,
I = electric current,
t = time
Quantisation of charge :charge is quantised. it means that charge on a body is always equal to the integral multiple of basic unit of charge i.e. charge of one electron.
Q = ne
e = 1.6 ×10^-19 C .
A charge of magnitude 1C contains about 6×10^18 electrons.
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M The following charges are located inside a submarine: 5.00μC,-9.00μC, 27.0μC , and -84.0μC (b) Is the number of electric field lines leaving the submarine greater than, equal to, or less than the number entering it?
Since the net electric flux which is − 6.89 × 10^6 V⋅m through the hull of the submarine is negative, the number of electric field lines leaving the submarine is less than the number entering it.
A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has the more limited underwater capability. Most large submarines consist of a cylindrical body with hemispherical (or conical) ends and a vertical structure, usually located amidships, that houses communications and sensing devices as well as periscopes. In modern submarines, this structure is the "sail".
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What is the position when t = 18 s?
S Show that the difference between decibel levels β₁ and β₂ of a sound is related to the ratio of the distances r₁ and r₂ from the sound source byβ₂ - β₁ = 20 log( r₁ / r₂)
Decibels are used to measure sound (dB). A motorcycle engine operating is roughly 95 dB louder than regular conversation, which is around 60 dB louder than a whisper.
What do you mean by decibel level?A relative unit of measurement, the decibel (symbol: dB), is equal to one-tenth of a bel (B). It uses a logarithmic scale to express the ratio of two values of a power or root-power quantity. The power ratio between two signals with a one-decibel difference in level is 101/10 (or roughly 1.26), and the root-power ratio is 10120. (approximately 1.12). The unit can convey an absolute value or a change in the relative value. When used in this method, the unit symbol is frequently followed by letter codes that denote the reference value. In the latter situation, the numeric value reflects the ratio of a value to a fixed reference value. A typical suffix is "V" for the reference value of 1 volt, for instance (e.g., "20 dB").
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the hydrogen-line emission spectrum includes a line at a wavelength of 434 nm. what is the energy of this radiation? (h
The energy of this radiation is 4.58 x 10⁻¹⁹ joules.
What is radiation?
Ionizing and non-ionizing categories of radiation are typically distinguished based on the energy of the radiated particles. Ionizing radiation carries energies greater than 10 eV, which is enough to ionize atoms and molecules and break chemical bonds. This distinction is important since these compounds differ significantly in how poisonous they are to living creatures. Ionizing radiation is typically produced by radioactive materials that release radiation in the form of photons, electrons, or positrons. Other sources include secondary cosmic rays that interact with Earth's atmosphere to produce muons, mesons, positrons, neutrons, and other particles, as well as X-rays from radiography examinations used in medicine.
Calculations:
wavelength = 434nm = 434 x 10⁻⁹m
planck's constant = h= 6.626 x 10 ⁻³⁴ J
E =?
by using the formula;
E = hc /λ
value for c is 3 x 10⁸ m/s
E is equal to (6.626 x 10 34 J)(3 x 108 m/s) / 434 x 109m.
E = 1.9878 x 10⁻²⁵ / 434 x 10⁻⁹m
E = 4.58 x 10⁻¹⁹ joules
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