Answer:
Hopefully, this is right.
Explanation:
Answer is 5.43.
A plate moves 2 km over a million years. A quarter of the way through this million-year timespan (at 250,000 years), the velocity was 5 mm/year.
Required:
What is the instantaneous velocity at 250,000 years and the finite velocity for the entire million-year timespan?
The instantaneous velocity of the plate at 250,000 years is 5 mm/year.
The finite velocity of the plate for the entire million-year timespan is 2 mm/year.
Instantaneous velocityThe instantaneous velocity is the rate of change of displacement with time. It measures the velocity at a specific period of time.
The instantaneous velocity of the plate at 250,000 years is 5 mm/year.
Finite velocityThe finite velocity of the plate for the entire million-year timespan is calculated as follows;
\(v = \frac{2 \ km}{1 \times 10^6 \ year} = \frac{2 \times 10^6 \ mm}{1 \times 10^6 \ year} = 2 \ mm/year\)
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An object has a mass of 450g. What is the gravitational force of the object by earth?
Answer:
4.41N or 4.5N (check explanation)
Explanation:
450g = 0.45kg
F = ma
Using 10m/s² = 10(0.45) = 4.5N
Using 9.8m/s² = 9.8(0.45) = 4.41N
The rainbow of visible colors in the electromagnetic spectrum varies continuously from the longest wavelengths (the reddest colors) to the shortest wavelengths (the deepest violet colors) our eyes can detect. Wavelengths near 655 nm are perceived as red. Those near 515 nm are green and those near 475 nm are blue. Calculate the frequency of light (in Hz) with a wavelength of 655 nm, 515 nm, and 475 nm.
HINT
(a)
655 nm
Hz
(b)
515 nm
Hz
(c)
475 nm
Hz
Answer:
The frequency of light can be calculated using the formula:
`c = λv`
Where `c` is the speed of light in a vacuum, `λ` is the wavelength of light, and `v` is the frequency of light.
The speed of light in a vacuum is `3.00 × 10^8 m/s`.
To convert the wavelength from nanometers to meters, we need to divide by `1 × 10^9`.
Thus, the frequency of light with a wavelength of 655 nm is:
`v = c/λ`
`v = (3.00 × 10^8 m/s)/(655 × 10^-9 m)`
`v = 4.58 × 10^14 Hz`
Therefore, the frequency of light with a wavelength of 655 nm is `4.58 × 10^14 Hz`.
Similarly, the frequency of light with a wavelength of 515 nm is:
`v = c/λ`
`v = (3.00 × 10^8 m/s)/(515 × 10^-9 m)`
`v = 5.83 × 10^14 Hz`
Therefore, the frequency of light with a wavelength of 515 nm is `5.83 × 10^14 Hz`.
Finally, the frequency of light with a wavelength of 475 nm is:
`v = c/λ`
`v = (3.00 × 10^8 m/s)/(475 × 10^-9 m)`
`v = 6.32 × 10^14 Hz`
Therefore, the frequency of light with a wavelength of 475 nm is `6.32 × 10^14 Hz`.
So, the frequency of light with a wavelength of 655 nm is `4.58 × 10^14 Hz`, the frequency of light with a wavelength of 515 nm is `5.83 × 10^14 Hz` and the frequency of light with a wavelength of 475 nm is `6.32 × 10^14 Hz`.
Two planets, Dean and Sam, orbit the Sun. They each have with circular orbits, but orbit at different distances from the Sun. Dean orbits at a greater average distance than Sam. According to Kepler's Third Law, which planet will have a longer orbital period? Group of answer choices Dean Sam Since they both have circular orbits, they will have the same orbital periods. There isn't enough information to tell.
Answer:
The correct answer is Dean has a period greater than San
Explanation:
Kepler's third law is an application of Newton's second law where the force is the universal force of attraction for circular orbits, where it is obtained.
T² = (4π² / G M) r³
When applying this equation to our case, the planet with a greater orbit must have a greater period.
Consequently Dean must have a period greater than San which has the smallest orbit
The correct answer is Dean has a period greater than San
Answer:
According to the law of universal gravitation, any two objects are attracted to each other. The strength of the gravitational force depends on the masses of the objects and their distance from each other.
Many stars have planets around them. If there were no gravity attracting a planet to its star, the planet's motion would carry it away from the star. However, when this motion is balanced by the gravitational attraction to the star, the planet orbits the star.
Two solar systems each have a planet the same distance from the star. The planets have the same mass, but Planet A orbits a more massive star than Planet B.
Which of the following statements is true about the planets?
A.
Planet B will keep orbiting its star longer than Planet A.
B.
Planet A has a longer year than Planet B.
C.
Planet A orbits its star faster than Planet B.
D.
Planet B is more attracted to its star than Planet A.
Explanation:
A roller coaster is at a peak of 20m and has a mass of 900kg. What is the potential energy of the roller coaster?
O 100000 J
10000 J
O 9.8 J
O 176400 J
The potential energy of the roller coaster is 176,400 J (joules).
The potential energy of an object is given by the formula PE = mgh, where PE is the potential energy, m is the mass of the object, g is the acceleration due to gravity, and h is the height or vertical position of the object.
In this case, the roller coaster is at a peak of 20m and has a mass of 900kg. The acceleration due to gravity, g, is approximately 9.8 \(m/s^2\).
Using the formula, we can calculate the potential energy:
PE = mgh
= (900 kg)(9.8 \(m/s^2\))(20 m)
= 176,400 J
Therefore, the potential energy of the roller coaster is 176,400 J (joules).
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Planet X has a mass m and a radius r. Planet Y has a mass ½ m and a radius ¼ r. An identical tennis ball of mass mt sits on both planets’ surfaces. How does the magnitude of the gravitational force on planet X compare to the magnitude of the gravitational force on planet Y?
The gravitational force on planet X is one-eight (¹/₈) of the magnitude of gravitational force on planet Y.
What is the gravitational force on both planets?
The gravitational force on each planet is directly proportional to the product of mass of the planet and the tennis ball and inversely proportional to the square of the radius of the planets.
F = GmM/r²
where;
G is universal gravitation constantm is the mass of the tennis ballM is the mass of the planetsr is the radius of the planetThe gravitational force on planet X is written as;
F_X = Gm(mt) / r²
where;
m is the mass of planet Xmt is the mass of the tennis ballr is the radius of the planet xThe gravitational force on planet Y is written as;
F_y = G(½m)(mt) / (¼r)²
F_y = ½(Gm(mt) / (¹/₁₆ r²)
F_y = (16 Gm mt)/(2r²)
F_y = 8(G m(mt) ) / r²
F_y = 8(F_X)
F_X = ¹/₈(F_Y)
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Which equation is most likely used to determine the acceleration from a velocity vs. time graph?
O a=
O m=
O a=
Om=
Δν
V₂-V1
X2-X1
AV
m
X2-X1
V₂-V1
The equation most likely used to determine acceleration from a velocity vs. time graph is a = Δv / Δt.
Acceleration is a fundamental concept in physics that refers to the rate at which an object's velocity changes over time. It is defined as the change in velocity divided by the change in time.
Mathematically, acceleration (a) is given by the equation:
a = Δv / Δt
where:
a represents acceleration
Δv represents the change in velocity (the difference between the final velocity and the initial velocity)
Δt represents the change in time (the difference between the final time and the initial time)
In this equation, "a" represents acceleration, Δv represents the change in velocity, and Δt represents the change in time. By calculating the ratio of the change in velocity to the change in time, we can determine the average acceleration over that time interval.
Therefore, The most likely equation used to calculate acceleration from a velocity vs. time graph is a = Δv /Δt.
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Indiana Jones is in a temple searching for artifacts. He finds a gold sphere with a radius of 2 cm sitting on a pressure sensitive plate. To avoid triggering the pressure plate, he must replace the gold with something of equal mass. The density of gold is 19.3.103 kg/m3, and the volume of a sphere is V = 4/3 Ar3. Indy has a bag of sand with a density of 1,602 kg/m3.
(A) What volume of sand must he replace the gold sphere with? If the sand was a sphere, what radius would it have?
Answer:
Volume of Sand = 0.4 m³
Radius of Sand Sphere = 0.46 m
Explanation:
First we need to find the volume of gold sphere:
Vg = (4/3)πr³
where,
Vg = Volume of gold sphere = ?
r = radius of gold sphere = 2 cm = 0.02 m
Therefore,
Vg = (4/3)π(0.2 m)³
Vg = 0.0335 m³
Now, we find mass of the gold:
ρg = mg/Vg
where,
ρg = density of gold = 19300 kg/m³
mg = mass of gold = ?
Vg = Volume of gold sphere = 0.0335 m³
Therefore,
mg = (19300 kg/m³)(0.0335 m³)
mg = 646.75 kg
Now, the volume of sand required for equivalent mass of gold, will be given by:
ρs = mg/Vs
where,
ρs = density of sand = 1602 kg/m³
mg = mass of gold = 646.75 kg
Vs = Volume of sand = ?
Therefore,
1602 kg/m³ = 646.75 kg/Vs
Vs = (646.75 kg)/(1602 kg/m³)
Vs = 0.4 m³
Now, for the radius of sand sphere to give a volume of 0.4 m³, can be determined from the formula:
Vs = (4/3)πr³
0.4 m³ = (4/3)πr³
r³ = 3(0.4 m³)/4π
r³ = 0.095 m³
r = ∛(0.095 m³)
r = 0.46 m
Part G
List several examples of applied force, normal force, and friction?
Examples of following forces mentioned -
Normal Force :- Book kept on the table , Girl standing on floor, ...infact every object experience a normal force in the universe.Applied Force :- this term literally means force responsible for the movements in the object or changes in the object , like throwing stones , playing ball , pushing an object , moving a pen from desk to chair..etc...Friction force :-Force responsible for the resistance in the flow of system's work , For example air resistance a type of obstruction experienced in air when a Paper ball is thrown from terrace of a society , Viscosity of honey is also an example of liquid friction / viscous drag...Sometimes friction is useful for the stability of universe. But some times its necessary. It is due to this force we walk without collapsing into the core of earth as earth is a market of gravitational field. To substantiate the field effect , friction is necessary to necessitate the life in planet. Rubbing of hands in winter season is also another example.To Know more about different forces -
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Voltage
Depends on the amount of resistance
Depends on the amount of current
Is the measurement of electrical pressure
All of the above
Voltage depends on the amount of resistance, current according to the Ohm's law, and, by definition, is the measurement of electrical pressure.
According to the Ohm's Law, the current through a conductor between two points is directly proportional to the voltage across the two points.
Mathematically,
V ∝ I
V = IR
where, R is the resistance of the conductor and I is the current flowing in the conductor. So, the voltage depends on the amount of resistance and current.
Also, Voltage is the pressure from an electrical circuit's power source that pushes charged electrons (current) through a conducting loop, enabling them to do work such as illuminating a light.
Hence All of the above option in the given question are true.
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A rifle can shoot a 4.00 g bullet at a speed of 998 m/s. Find the kinetic energy of the bullet. What work is done on the bullet if it starts from rest?
Answer:
1992.008J
Explanation:
A point object moves from point A to point B along a circular path with a radius. What is the size of the angle ?
The size of the angle θ of a point object moving from point A to point B along a circular path is 2πR / L.
How to solve size of an angle?To understand this, consider a simple example. Suppose that a point object that moves from point A to point B along a circular path with a radius of 1 meter. The distance between points A and B is also 1 meter. Therefore, the size of the angle θ is equal to 2π × 1 / 1 = 2π radians.
In general, the size of the angle θ = ratio of the circumference of the circle to the distance between points A and B. The circumference of the circle is equal to 2πR, where R = radius of the circle. Therefore, the size of the angle θ is equal to 2πR / L.
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Complete question:
A point object moves from point A to point B along a circular path with a radius R. What is the size of the angle θ?
In a DC generator, the generated emf is directly proportional to the
In a DC generator, the generated electromotive force (emf) is directly proportional to the rotational speed of the generator's armature and the strength of the magnetic field within the generator.
This relationship is described by the equation for the generated emf in a DC generator:
Emf = Φ * N * A * Z / 60
Where:
Emf is the generated electromotive force (in volts),
Φ is the magnetic flux density (in Weber/meter^2\(meter^2\) or Tesla),
N is the number of turns in the armature winding,
A is the effective area of the armature coil (in square meters),
Z is the total number of armature conductors, and
60 is a constant representing the conversion from seconds to minutes.
From this equation, we can see that the generated emf is directly proportional to the magnetic flux density (Φ) and the product of the number of turns (N), effective area (A), and the total number of armature conductors (Z). This means that increasing any of these factors will result in a higher generated emf.
The magnetic flux density (Φ) can be increased by using stronger permanent magnets or increasing the strength of the field windings in the generator.
The number of turns (N) and the effective area (A) are design parameters and can be optimized for a specific generator. Increasing the number of turns or the effective area will result in a higher generated emf.
Similarly, the total number of armature conductors (Z) can be increased to enhance the generated emf.
By controlling and optimizing these factors, the generated emf in a DC generator can be increased, resulting in higher electrical output. However, it is important to note that there are practical limits to these factors based on the design and construction of the generator.
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The process of making alloys involves pure metals to remove impurities. Then the pure metals are with other components.
The process of making alloys involves the use of pure metals to remove impurities and then combining the purified metals with other components to create a desired alloy with specific properties.
Alloys are metallic substances that are composed of two or more elements, with at least one of them being a metal. The process of making alloys typically involves several steps to ensure the desired composition and properties are achieved.Removing impurities: The first step in making alloys is to obtain pure metals. Pure metals are often extracted from ores and undergo processes such as smelting or refining to remove impurities. This purification step is important to ensure the resulting alloy has consistent properties.Composition determination: Once the pure metals are obtained, their composition is determined based on the desired alloy's characteristics. This involves considering factors such as strength, hardness, corrosion resistance, electrical conductivity, and other specific properties required for the intended application.Mixing and melting: The pure metals, along with other components or alloying elements, are mixed together in precise proportions. Alloying elements can be other metals or non-metals, such as carbon. The mixture is then heated to a high temperature to melt the metals and ensure uniform mixing.Homogenization: After melting, the alloy is typically subjected to a process called homogenization. This involves holding the molten alloy at a specific temperature for a period of time to allow for diffusion and ensure a consistent distribution of the alloying elements throughout the mixture.Cooling and solidification: Once the homogenization is complete, the molten alloy is cooled down. The cooling rate can influence the microstructure and properties of the alloy. Controlled cooling techniques may be employed to achieve specific characteristics, such as fine-grained structures or desired phase transformations.Further processing: The solidified alloy can undergo additional processes such as forging, rolling, extrusion, or heat treatment to further refine its properties and shape it into the desired final product.By following these steps, the process of making alloys ensures the removal of impurities from pure metals and the combination of those metals with other components to create alloys with specific properties suitable for various applications.For more such questions on Alloys, click on:
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Which is more accurate slope o average?
Explain the process of refraction of light
The process of refraction of light occurs when light rays bends when travelling between media of different densities.
What is refraction of light?
Refraction of light is the bending of light rays or the change in the direction of light rays as it travels between media of different densities.
Light waves travel faster in media of less density than media of more density.
The change in density of the media makes light waves to be bend towards or away from the normal.
For example, when light travels from less dense air to more dense water, the light rays are bent towards the normal. However, when light rays travel from water to air, the light rays are refracted away from the normal.
In conclusion, refraction of light waves occur when light crosses the boundary of media of different densities.
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What feature does not require a planet to have any particular characteristics?
Stream Beds
Dunes
Impact Craters
Volcanic Lava Flows
What is the correct answer?
Answer:
Impact Craters.
Explanation:
An impact crater can be defined as a circular depression that is caused by impact on any planet or asteroids or any other celestial body's surface. When smaller body in galaxy impacts these larger bodies, they form a circular depression on it's surface.
This is a major feature found in solid object such as the Moon, Mercury, etc.
Therefore, the feature that a planet does not require is an impact crater. As other features are important to define a planet. Thus correct option is C.
WILL GIVE BRAINLIEST
Lucas is carrying his rock collection into class. He carries 30 pounds of rare rocks 15 feet into Classroom 6. It takes him
3 minutes to get them into the classroom What is Lucas's speed and level of work? Be sure to show your work with
equations as part of your answer.
Answer:
10 and 5
Explanation:
Answer:
It is given that,
Force, F = 30 pounds = 133.4 N
Distance, d = 15 feet = 4.572 m
Time taken, t = 3 minutes = 180 seconds
Lucas's speed is given by the ratio of total displacement divided by total time taken. It is given by :
s = 0.0254 m/s
So, her speed is 0.0254 m/s.
Work done, W = F . d
W = 133.4 N × 4.572 m
W = 609.90 J
or
W = 610 J
Hence, this is the required solution.
Two objects are held close together. When they are released, they move toward one another. Which conclusion is supported by this evidence? O The objects are both positively charged. O The objects are both negatively charged. O The objects have no charge. O The objects have opposite charges. Mark this and return Save and Exit 02:48:18 Next Submit
Two objects are held close together. When they are released, they move toward one another. The conclusion is supported by this evidence is the objects have opposite charges.
An electric charge is a physical property that causes matter to experience a force when in close proximity to other electrically charged matter. There are two types of electric charges: positive and negative. Protons, which are positively charged, and electrons, which are negatively charged, are subatomic particles that make up matter.
In general, the protons and neutrons in the nucleus of an atom have a net positive charge, while electrons, which orbit the nucleus, have a net negative charge. The charges of these subatomic particles are indicated by the symbols "p" for proton, "n" for neutron, and "e" for electron.
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a student is designing an experiment in which an object of unknown mass is pushed across a frictionless surface
The applied force must be larger than the frictional force for a body to move successfully.
What is friction?Between two surfaces that are sliding or attempting to slide over one another, there is a force called friction. For instance, friction makes it challenging to push a book down the floor. Friction always moves an object in a direction that is counter to the direction that it is traveling or attempting to move.
When a body is pushed, an exact quantity of frictional force is created, up until the point where Fs max = coefficient of friction * normal force.
After that, when fs max exceeds the frictional force, dynamic friction enters the picture, which is what causes the body to move.
The body begins to move after a force is applied that is more than the minimal need, or what we refer to as the Threshold (f applied > fs max).
In the case of a frictionless surface, the applied force will be perpendicular to the gravitational force that is being taken into account. Even the slightest acceleration must cause the body to move.
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place the following structures in the appropriate category based on their location in a cell
Answer:
Cell surface.
CiliumPlasma membraneMicrovilus.
Nucleus
Cellular DNANucleolusChromosome.
Cytoplasm
MitochondriaGolgi apparatusCytoskeleton.
Estimate the gravitational force of attraction between two people sitting side by side on a park bench. How does this force compare with the gravitational force exerted on each of them by the Earth
Weight is compared with the gravitational force exerted on each of them by the Earth.
What is Newton's law of gravitation?Newton's law of gravity states that each particle having mass in the universe attracts each other particle with a force known as the gravitational force.
The gravitational force is proportional to the product of the masses of the two bodies and inversely proportional to the square of their distance.
When mass increases and distance reduces, gravity rises. Gravity also lowers when the distance between two points grows and the mass decreases.
The gravitational force is balanced by weight;
\(\rm F = W \\\\ G\frac{mM}{r^2} =mg\)
Hence, weight is compared with the gravitational force exerted on each of them by the Earth.
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Please help !!
Urgent !
The options are the same for the questions
Answer:
it have magnitude and direction is vector
it have magnitude but not direction is scalar
by multiplying ..... is magnitude
ny adding you get another vector
Explanation:
yeah I hope this helpa
differentiate between speed and velocity
Explanation:
Speed - The rate at which something moves
Velocity - The speed of something in a specific direction
Velocity is kind of a specific type of speed.
Which person will most likely hear the loudest sound?
A
B
C
D
Answer:
The youngest person
Explanation:
Hearing worsens with age
Please mark brainliest
Answer:
A
Explanation:
The person closest to the origin of the sound will most likely hear the loudest sound. ^^
are physical quantities and fundamental quantities same
Answer:
The physical quantities are the quantities that are the base quantities of the measurement. They are known as the fundamental quantities. The units of those units are known as the fundamental units. The derived physical quantities are dependent on the fundamental quantities.
A projectile leaves the ground at 150 m/s and reaches a maximum height of 0.57 km. If there was no air resistance, at what angle above the horizontal did it leave the ground?
The projectile left the ground at an angle of 67.4 degrees above the horizontal, if there was no air resistance.
First, let's find the time of flight. We can use the kinematic equation:
y = yo + voy*t + 0.5*a*t^2
where y is the maximum height (0.57 km), yo is the initial height (0 m), voy is the initial vertical velocity (unknown), a is the acceleration due to gravity (-9.81 m/s^2), and t is the time to reach the maximum height (unknown).
Plugging in the values and solving for t, we get:
0.57 km = 0 + voy*t + 0.5*(-9.81 m/s^2)*t^2
t = 12.19 seconds
Since the total time of flight is twice the time to reach the maximum height, we have:
total time of flight = 2*t = 24.38 seconds
Now we can use the range equation to find the initial velocity vector of the projectile:
x = vox*t
1500 m = vox*24.38 seconds
vox = 61.51 m/s
where x is the range and vox is the initial horizontal velocity.
Finally, we can use trigonometry to find the initial angle of projection, theta:
voy/vox = tan(theta)
voy = vox*tan(theta)
61.51 m/s*tan(theta) = (150 m/s)
theta = 67.4 degrees
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A tennis player moves in a straight-line path as shown in the figure below. Find her average velocity in the following time intervals.A coordinate plane has a horizontal axis labeled t (s) and a vertical axis labeled x (m). The horizontal axis ranges from 0 to 6 s and the vertical axis ranges from −4 m to 6 m.A line enters the viewing window from the origin and moves up and to the right until it reaches (1, 4).The line then moves down and to the right until it reaches (2.5, −2).The line then moves horizontally to the right until it reaches (4, −2).The line then moves up and to the right until it reaches (5, 0).(a) 0 to 1.0 s m/s(b) 0 to 4.0 s m/s(c) 1.0 s to 5.0 s m/s(d) 0 to 5.0 s m/s
Since velocity = distance/time, when distance is plotted against time on a graph, the velocity at any moment is represented by the slope of the graph (the tangent if velocity is not linear, but that's not the case here).
Let's calculate the slopes of the graph in each separate section:
0 to 1: 4m/1s = 4m/s
1 to 2.5: -6m/1.5s = -4m/s
2.5 to 4: 0m/s (graph's tangent is 0 here)
4 to 5: 2m/1s = 2m/s
Now that we have the velocities in each section, we can calculate the averages. To calculate the average between multiple sections, multiply each velocity by the number of seconds the graph is at that velocity, take the sum of those values, then divide by the total number of seconds in the interval.
(a) 0 to 1s: we already calculated this; 4m/s
(b) 0 to 4s: (4m/s * 1s + -4m/s * 1.5s + 0m/s * 1.5s) / 4s = (4-6)/4 = -2/4 = -0.5m/s
(c) 1 to 5s: (-4m/s * 1.5s + 0m/s * 1.5s + 2m/s * 1s) / 4s = (-6+2)/4 = -4/4 = -1m/s
(d) 0 to 5s: (4m/s * 1s + -4m/s * 1.5s + 0m/s * 1.5s + 2m/s * 1s) / 5s = (4-6+2)/5 = 0/5 = 0m/s
who plays among us?????
Answer:
i do
Explanation:
What becomes V if we use 2 resistors of 4W in parallel?
A. 2.66 V
B. 6 V
C. 12 V
D. 24 V
Explanation:
The question is incomplete. To get the voltage V across the resistors, we need to total current flowing in the circuit.
Let the current I = 6 A
According to ohms law, V = IRt
V is the total voltage
I is the total current
Rr is the total effective resistance
Since the 2 4ohms resistors are connected in parallel;
1/Rt = 1/4 + 1/4
1/Rt = 2/4
Cross multiply
2Rt = 4
Rt = 4/2
Rt = 2 ohms
Get the voltage V.
V = IRt
V = 6(2)
V = 12V
Hence the required voltage will be 12V
Note that the value of the current used was assumed. The same calculation can be employed for any value of the current