A 1. 2 kg block is held at rest against the spring with a force constant k= 730 N/m. Initially, the spring is compressed a distance d. When the block is released, it slides across a surface that is frictionless except for a rough patch of width 5. 0 cm that has a coefficient of kinetic friction = 0. 44. Find d, such that the block's speed after crossing the rough patch is 2. 3 m/s

The wavefunction number for the specified function is:Ψ(x) = [tex][2/(\alpha (1 - e^{(-4nm/\alpha )))}]e^{(-x/\alpha )}[/tex]

The wavefunction given is:

Ψ(x) = A[tex]e^{(-x/\alpha )}[/tex]

where Ψ(x) is the wavefunction, A is a constant, x is the position of the electron and α is a constant with units of length.

The normalization condition is:

∫|Ψ(x)|² dx = 1

Since Ψ(x) is zero outside the range (0, 2nm), the integral can be simplified to:

∫[tex]0^(2nm)|Ae^{(-x/\alpha )}|[/tex] ²dx = 1

Simplifying the integral further:

[tex]|A|^{2} (-\alpha /2) (e^{(-4nm/\alpha ) - 1)} = 1[/tex]

Since the wavefunction is normalized, |A|² is equal to the inverse of the integral above. Solving for |A|², we get:

|A|² = [tex][-2/(\alpha (e^{(-4nm/α) - 1))}][/tex]

Thus, the wavefunction is:

Ψ(x) = [tex][2/(\alpha (1 - e^{(-4nm/\alpha )))}]e^{(-x/\alpha )}[/tex]

So, the value of the wavefunction for this given function is:

[tex][2/(\alpha (1 - e^{(-4nm/\alpha )))}]e^{(-x/\alpha )}[/tex]

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The weight of a 65 kg person standing on the moon with a mass of 7.348e22 kg and a radius of 1738 km would be approximately 105.3 N.

The weight of a 65 kg person on the moon can be calculated using the formula:

Weight = mass x gravitational acceleration

where mass is the mass of the person, and gravitational acceleration is the acceleration due to gravity on the surface of the moon.

The gravitational acceleration on the surface of the moon is given by:

g = G*M/R^2

where G is the gravitational constant, M is the mass of the moon, and R is the radius of the moon.

In this case, the mass of the moon is M = 7.348e22 kg, and the radius of the moon is R = 1738 km = 1.738e6 m. The gravitational constant is G = 6.6743e-11 Nm^2/kg^2.

So, the gravitational acceleration on the surface of the moon is:

g = G*M/R^2 = (6.6743e-11 Nm^2/kg^2) x (7.348e22 kg) / (1.738e6 m)^2

= 1.62 m/s^2

Now, we can calculate the weight of a 65 kg person on the moon:

Weight = mass x gravitational acceleration

= 65 kg x 1.62 m/s^2

= 105.3 N

Therefore, a 65 kg person would weight about 105.3 N on the surface of the moon.

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The required object A is moving at a speed of 2.62846 m/s at the end of the ramp.

To determine the speed of object A at the end of the ramp, we can use the principles of conservation of energy and rotational motion.

Given:

First, let's calculate the potential energy (PE) of object A at the beginning of the ramp. The potential energy can be given by:

PE = m * g * h,

PE = 0.115  * 9.8  * 0.14  = 0.1628 J

At the end of the ramp, the potential energy is fully converted into kinetic energy (KE). The kinetic energy can be given by:

KE = (1/2) * I * ω²,

For a solid sphere rolling without slipping, the moment of inertia (I) can be given by:

I = (2/5) * m * r²,

I = (2/5) * 0.115 kg * (0.17 m)² = 0.00132 kg·m²

Now, we can relate the linear speed (v) and the angular velocity (ω) of the rolling object. For a solid sphere rolling without slipping, the relationship is:

v = ω * r,

ω = v / r.

Next, we equate the potential energy at the beginning of the ramp to the kinetic energy at the end of the ramp:

PE = KE

m * g * h = (1/2) * I * ω²

0.115 * 9.8  * 0.14  = (1/2) * 0.00132 * (v / r)²

0.115 * 9.8  * 0.14 = 0.00132/2 * (v / 0.17 )²

v = 2.62846

Therefore, object A is moving at a speed of 2.62846 m/s at the end of the ramp.

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The type of reflection occurring when light hits a surface can be determined by observing how the light is scattered.

Specular reflection occurs when light is reflected at a single angle, resulting in a clear and focused reflection. On the other hand, diffuse reflection occurs when light is scattered in many directions, producing a blurred or hazy reflection.

In the case of water reflecting light, it is likely that the reflection is a combination of both specular and diffuse reflection. When the water surface is smooth and still, light is reflected at a specific angle, resulting in a clear and focused reflection.

This is specular reflection. However, when the surface of the water is disturbed, the reflection becomes scattered and blurred, which is characteristic of diffuse reflection.

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To find the speed of the green and blue pucks after the collision, we can use the conservation of momentum and the conservation of energy equations and it is 3.33 m/s and  2.78 m/s respectively.

First, let's find the mass of the blue puck. If the mass of the blue puck is 20% greater than the mass of the green one, then:

m (blue) = 1.2 * m (green)

Next, let's use the conservation of momentum equation:

m (green) * v (green), initial + m (blue) * v (blue), initial = m (green) * v (green), final + m (blue) * v (blue), final

Since the pucks approach each other with equal and opposite momenta, we can set v (blue), initial = -v (green), initial = -10 m/s. Plugging in the values we know:

m (green) * 10 + 1.2 * m (green) * (-10) = m (green) * v (green), final + 1.2 * m (green) * v (blue), final

Next, let's use the conservation of energy equation. If half the kinetic energy is lost during the collision, then:

0.5 * m (green) * v (green), initial2 + 0.5 * m (blue) * v (blue), initial2 = 0.5 * (m (green) * v (green), final2 + m (blue) * v (blue), final2)

Plugging in the values we know:

0.5 * m (green) * 102 + 0.5 * 1.2 * m (green) * (-10)2 = 0.5 * (m (green) * v (green), final2 + 1.2 * m (green) * v (blue), final2)

Now we can solve for the final velocities of the pucks using these two equations. We get:

v (green), final = -3.33 m/s
v (blue), final = 2.78 m/s

Therefore, the speed of the green puck after the collision is 3.33 m/s and the speed of the blue puck after the collision is 2.78 m/s.

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Answer:

Jwbsbsbdjeiskbsj3kabajj2jjj1jj2j2j3jkkkk3j3j2

To find the wavelength of the wave along the string, we first need to measure the distance between two consecutive points on the wave that are in the same phase.

We can look at the graph provided by the question, whose full cycle of the wave completes in 0.1sec, i.e. demonstrating that this is a complete up and down movement of the point.

As measured in the graph, we see that the distance between two consecutive points is 0.5 cm. Then we calculate the wavelength of the wave using the following formula:

Therefore, the wavelength of the wave corresponds to 0.005m.

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Figure 1 shows a 5.4 N force pushing two gliders along an air track. The 160 g spring between the gliders is compressed. The spring is firmly attached to the gliders and does not sag. This situation demonstrates Hooke’s Law, which states that the force required to compress a spring is directly proportional to the amount of displacement of the spring. In this case, the 5.4 N force is pushing the gliders towards each other, compressing the spring and causing a displacement. As Hooke's Law states, the greater the force used to compress the spring, the greater the displacement will be.

The stiffness of the spring in this situation would be determined by the spring constant, which can be calculated using the formula F = -kx. The spring constant can be calculated by using the displacement of the spring.

When the 5.4 N force is applied, the kinetic energy of the gliders is converted into potential energy, which is stored in the compressed spring. When the force is removed, the potential energy is converted back into kinetic energy and the gliders move away from each other.

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The apprοximate speed οf the rοller cοaster at the bοttοm οf the track is 31.6 m/s.

It is defined as the distance travelled by an οbject per unit time, and is usually expressed in meters per secοnd (m/s) οr οther units οf distance per unit time (such as miles per hοur οr kilοmeters per hοur).

Nο, the speed οf the rοller cοaster at the bοttοm οf the track is nοt 45 m/s.

Tο determine the speed οf the rοller cοaster at the bοttοm οf the track, we can use the principle οf cοnservatiοn οf energy, which states that the tοtal amοunt οf energy in a clοsed system remains cοnstant.

At the tοp οf the track, the rοller cοaster has οnly pοtential energy, which can be calculated as: PE = mgh

where m is the mass οf the rοller cοaster, g is the acceleratiοn due tο gravity (apprοximately 9.81 m/s²), and h is the height οf the track (51 meters). Assuming the mass οf the rοller cοaster is 1 kilοgram, the pοtential energy at the tοp οf the track is :

[tex]PE = (1 kg)(9.81 m/s^2)(51 m) = 502.31 J[/tex]

At the bottom of the track, all of the potential energy has been converted to kinetic energy, which can be calculated as:

[tex]KE = 1/2 mv^2[/tex]

where v is the speed of the roller coaster. Equating the initial potential energy to the final kinetic energy, we have:

PE = KE

[tex]mgh = 1/2 mv^2Solving for v, we get:v = sqrt(2gh)v = sqrt(2 x 9.81 m/s^2 x 51 m) = sqrt(999.162) = 31.6 m/s (approximately)[/tex]

Therefore, the approximate speed of the roller coaster at the bottom of the track is 31.6 m/s.

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mass of dog and boat are m = 4.5 kg, and M = 18 kg respectively.

Initial distance of dog from the shore, D = 4.5 m

In the 50/30/20 rule, 50 represents the percentage of your after-tax income that you should allocate towards your essential expenses.

These are the necessary expenses that you need to pay for in order to live, such as housing, utilities, groceries, transportation, and healthcare. By allocating 50% of your after-tax income towards these essential expenses, you can ensure that you are meeting your basic needs and maintaining a stable lifestyle.

The other percentages in the 50/30/20 rule refer to the remaining portions of your after-tax income. 30% should be allocated towards your discretionary spending, which includes non-essential expenses such as entertainment, dining out, travel, and hobbies. The final 20% should be allocated towards your financial goals, such as paying off debt, building an emergency fund, and saving for retirement or other long-term goals.

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a) In a series circuit, the current remains the same throughout, so the current in the ammeter A1 is the same as the current in the ammeter A3. Therefore, the readings of A1 and A3 should be the same.

b) As mentioned in the previously, the readings of A1 and A3 should be the same since they are measuring the same current.

c) To determine the reading of the voltmeter V1, we need to know the current passing through it and the resistance between its two points. Since the circuit contains only resistors, we can apply Ohm's law to calculate the total resistance of the circuit.

The total resistance of the circuit can be calculated as follows:

Total Resistance = 9 x 3Ω (since there are nine 3Ω resistors connected in series)

Total Resistance = 27Ω

Since the current in the ammeter A1 is 1 ampere, the voltage across the voltmeter V1 can be calculated using Ohm's law:

V1 = I x R

V1 = 1 x 27

V1 = 27 volts

Therefore, the reading of the voltmeter V1 should be 27 volts.

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580 nm light shines on a double slit with d=0. 000125 m. the angle of the third dark interference minimum(m=3) is 0.76 degrees.

The angle θ of the third dark interference minimum can be calculated using the equation:

sin θ = (m λ) / d

where m is the order of the interference minimum, λ is the wavelength of the light, and d is the distance between the slits.

In this case, m = 3, λ = 580 nm = 5.80 × 10^−7 m, and d = 0.000125 m. Plugging in these values, we get:

sin θ = (3 × 5.80 × 10^−7 m) / 0.000125 m

solving this, we get:

sin θ = 0.0132

Taking the inverse sine of both sides, we get:

θ = sin−1 (0.0132)

Using a calculator, we find:

θ ≈ 0.76 degrees

Therefore, the angle of the third dark interference minimum is approximately 0.76 degrees.

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True, The motion of an object changes only when a(n) net force acts on it according to Newton’s first law.

Newton's first law of motion, also known as the law of inertia, states that an object at rest will remain at rest, and an object in motion will remain in motion with a constant velocity, unless acted upon by a net external force.

No, according to Newton's first law of motion, an object in motion will continue to move with a constant velocity only if there is no net external force acting on it. Any change in motion requires the application of a net force.

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Therefore, the mass of ball 2 is approximately 24.7 kg.

A collision is an event that occurs when two or more objects come into contact with each other in a way that alters their motion. In physics, collisions are studied in terms of the conservation of momentum and the conservation of kinetic energy. In an elastic collision, the total kinetic energy of the system is conserved, and the objects bounce off each other without any loss of energy. In an inelastic collision, some of the kinetic energy is converted into other forms of energy, such as heat or sound, and the objects may stick together after the collision. Collisions can be categorized into two types: head-on collisions and oblique collisions. In a head-on collision, the objects approach each other directly from opposite directions, while in an oblique collision, the objects approach each other at an angle. Collisions are an important concept in physics and have applications in fields such as engineering, transportation, and sports. Understanding the principles of collisions can help us design safer cars, improve the performance of athletic equipment, and develop new technologies for space exploration.

Here,

We can use the conservation of momentum and the conservation of kinetic energy to solve for the mass of ball 2 in the completely elastic collision. Using the conservation of momentum:

m1v1i + m2v2i = m1v1f + m2v2f

Substituting the known values:

(6.7 kg)(2.0 m/s) + m2(-5.0 m/s) = (6.7 kg)(-6.18 m/s) + m2(0.83 m/s)

Simplifying and solving for m2:

(13.4 - 33.9) kg·m/s = -44.006 kg·m/s + 0.83 m2

-20.5 kg·m/s = 0.83 m2

m2 = (-20.5 kg·m/s) / (0.83 m/s)

m2 ≈ 24.7 kg

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The correct answer is C i.e, . motion of a wave source perpendicular to the line of sight cannot cause a wavelength shift because such motion doesn't make peaks of waves closer together or farther apart.

The Doppler effect is the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source. In the case of detecting radial velocity, the observer and the wave source are either approaching or moving away from each other along the line of sight. This causes the wavelength of the observed waves to either compress or stretch, which results in a shift in frequency or color.

Option C is correct because motion perpendicular to the line of sight does not cause compression or stretching of the wavelength, which means that there is no change in frequency or color of the waves observed. Therefore, only radial velocity can be detected through the Doppler effect. Option A is also partially correct, as it is harder to measure the wavelength shift accurately for motion perpendicular to the line of sight. However, the reason for this is the lack of change in the wavelength, not the difficulty of measuring it. Option B is incorrect, as objects can have motion perpendicular to the line of sight. Option D is also incorrect, as objects moving at angles other than directly towards or away from the observer can still emit waves that can be detected.

The wavelength is not compressed or stretched by motion perpendicular to the line of sight, so there is no change in the frequency or colour of the waves that can be seen, making option C the right one.

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Shear stress is tangential tension that results from fluid moving against resistance against a solid surface.  therefore (iii) > (i)  = (ii) option  a).

An item experiences deformation when an exterior force works upon it. if the force's orientation is parallel to the object's surface. Along that line, there will be a distortion. The item in this instance is under tensile or tangential tension.

The stress an object experiences is known as shearing stress or tangential stress when the path of the deforming force or exterior force is parallel to the cross-sectional area.

Shear stress results from forces that are parallel to and reside in the plane of the cross-sectional area, whereas normal stress results from forces that are perpendicular to a cross-sectional area of the substance.

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The correct answer is A. Potential energy is converted to kinetic energy.

At point C, the pendulum has reached its maximum displacement on the other side of its swing. At this point, the pendulum's velocity is zero, so its kinetic energy is also zero. However, the pendulum's height above its rest position is at its maximum, so its potential energy is at its maximum.

As the pendulum swings back toward its rest position, its potential energy will be converted back into kinetic energy. At the bottom of the swing (point A), the pendulum's potential energy will be at its minimum, and its kinetic energy will be at its maximum.

Therefore, the correct answer is: Potential energy is converted to kinetic energy.

What is Potential energy?

Potential energy is a form of energy that an object possesses due to its position or state. It is stored energy that can be converted into other forms of energy, such as kinetic energy, or released in a variety of ways.

What is kinetic energy?

Kinetic energy is a form of energy that an object possesses due to its motion. It is the energy an object has because of its motion, mass, and velocity. The faster an object moves and the more massive it is, the greater its kinetic energy will be.

The formula for kinetic energy is:

KE = 1/2 * m * v^2

where KE is kinetic energy, m is the mass of the object, and v is the velocity of the object.

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Answer:

Explanation:

The reson that the north of the compas pin points in that direction is because ,that is Earth magnetic south pole is and that is where they attract

An excellent green, eco-friendly substitute is coconut coir, a byproduct of coconuts. Due to its ability to clean without endangering the ecosystem, coir is becoming increasingly popular and adopted.

The shell of the coconut is known as coco coir. It is immersed in water for a few weeks after extraction to help it loosen and soften. The husk is then dried, brushed, and turned into a product that resembles fibre but is much stronger. Because of the product's durability, stretching or compressing it in any way won't harm it.
Fine brushes, ropes, beds, upholstery, and fishnets are all made from white coco coir, which is extracted from unripe coconuts.

Brown coco coir is pressed from ripe coconuts and used to create mats, pots, and scrubbers that resemble discs for cleaning kitchen surfaces and utensils. In the kitchen, these naturally antimicrobial items are preferable to plastic scrubbers. When they begin, they can be recycled as an organic planting substrate because they are not toxic.

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Answer:

1.63 m

Explanation:

difference between the length of iron rod and brass rod must remain same, writing it in the equation form

[tex]l_{iron} - l_{brass} = C[/tex]

where C is a constant, differentiation both sides with respect to temperature([tex]\theta[/tex]),

[tex]\dfrac{dl_{iron}}{d\theta} - \dfrac{dl_{brass}}{d\theta} = 0[/tex]  ...  (1)

According to linear expansion equation,

[tex]\dfrac{dl}{d\theta} = \alpha l_0[/tex]

where [tex]l_0[/tex] is the length at 0 degree Celsius.

Now,

substituting values in equation 1 we get,

[tex]\alpha_{iron}. l_{iron} - \alpha_{brass} . l_{brass} = 0[/tex]

substituting the values of respective coefficient and length of iron at 0 degree Celsius we get,

[tex]l_{brass} = 1.63[/tex] m

Hopefully, this answer helped you solve the question!

The answer is a salt. Salts are ionic compounds that are composed of positively and negatively charged ions.

When dissolved in water, the ions separate and the salt dissolves. Salts also have a high melting point and when heated, they decompose into their constituent elements, producing a flame. This is a chemical property known as thermal decomposition.Thermal decomposition is a type of chemical decomposition induced by the application of heat. It is a specific type of chemical decomposition in which molecules of a compound are broken down into smaller molecules or elements. Thermal decomposition is often used in industry to produce useful chemicals, such as chlorine from table salt, and for the production of metals and alloys from ore.

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The electrostatic force between the negatively charged rod and the metal can will increase when additional negative charges are added to the rod, while the gravitational force between them will remain the same.

This is because the electrostatic force between the rod and the can is proportional to the charge on the rod and the distance between them, according to Coulomb's law. Adding additional negative charges to the rod increases its total charge, which in turn increases the electrostatic force between the rod and the can.

On the other hand, the gravitational force between the rod and the can is determined by their masses and the distance between them, according to the law of gravitation. Since neither the mass nor the distance between the rod and can changes in this experiment, the gravitational force remains the same.

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Answer:

The main function of a producer in an ecosystem is to make sugar through photosynthesis. Producers are organisms, such as plants and algae, that produce their own food using energy from sunlight, carbon dioxide from the air, and nutrients from the soil or water. Through the process of photosynthesis, producers convert light energy into chemical energy in the form of sugar, which can be used as a source of food and energy by other organisms in the ecosystem. This makes producers a critical component of the food chain and the foundation of many ecosystems. Options A, B, and D do not accurately describe the main function of a producer in an ecosystem.

The toy car is moving at a speed of approximately 5.74 m/s after it has been pushed for a distance of 2 meters.

The principle of conservation of energy can be used to solve the problem.

The initial kinetic energy of the car is 25 J, and the final kinetic energy of the car is (1/2) * 2 kg * (5.74 m/s)^2, which is approximately 40.97 J.

To solve this problem, we can use the principle of conservation of energy, which states that the initial kinetic energy of the toy car is equal to the final kinetic energy of the car after it has been pushed for a distance of 2 meters.

The initial kinetic energy of the car is given by:

KE1 = (1/2) * m * v1^2

where m is the mass of the car (2 kg), and v1 is the initial velocity of the car (5 m/s).

KE1 = (1/2) * 2 kg * (5 m/s)^2

KE1 = 25 J

The final kinetic energy of the car is given by:

KE2 = (1/2) * m * v2^2

where v2 is the final velocity of the car after it has been pushed for a distance of 2 meters.

Since the car has been pushed by an external force, work is done on the car, and this work is equal to the change in kinetic energy of the car. The work done on the car is given by:

W = F * d

where F is the force applied on the car, and d is the distance the car has been pushed. Since the car is moving horizontally, the force applied on the car is in the same direction as its motion, so the work done on the car is equal to the change in kinetic energy of the car.

W = KE2 - KE1

Substituting the values we get:

W = (1/2) * 2 kg * v2^2 - 25 J

W = (1/2) * 2 kg * v2^2 - 25 J = F * d = (2 kg * a) * 2 m = 4 kg m/s^2 * 2 m = 8 J

Solving for v2 we have:

v2 = sqrt((2 * (W + KE1)) / m)

v2 = sqrt((2 * (8 J + 25 J)) / 2 kg)

v2 = sqrt(66 J / 2 kg)

v2 = sqrt(33) m/s

Therefore, the toy car is moving at a speed of approximately 5.74 m/s after it has been pushed for a distance of 2 meters.

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When the ball on the left is pulled to the side and released, it will swing back and hit the ball on the right. Upon impact, the momentum of the left ball will be transferred to the right ball, causing the right ball to start swinging to the right while the left ball will come to a stop.

Therefore, the correct answer is: "The ball on the right will swing to the right." Option C

In physics, momentum is a property of moving objects that is determined by both their mass and velocity. It is defined as the product of an object's mass and velocity, and it is a vector quantity, which means it has both magnitude and direction.

Mathematically, momentum (p) is expressed as:

p = m * v

where m is the mass of the object and v is its velocity.

Momentum is conserved in a closed system, meaning that the total momentum of the system remains constant unless an external force acts on it. This is known as the law of conservation of momentum, which is a fundamental principle of physics. The law of conservation of momentum has many practical applications, from understanding the behavior of collisions in billiards or car accidents, to designing spacecraft trajectories, to studying the behavior of subatomic particles

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If you cut a wire directly and squarely across its width, the end will look like a circle. The cross sectional is the area of that end.

If you cut a wire directly and squarely across its width, the end will look like a circle. The cross sectionarea is Pi x r2, which is the area of that end. When the wire type is the same, a larger cross section area results in lower resistance per foot.

It is assumed that the cross's length and area The conductor's section is doubled. This means that the new length and cross sectional area are both 2l and 2A. As a result, the new resistance of the conductor is R′=2l2A=lA.

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Answer:

all of these

Explanation:

D. all of these is the correct answer