Explain what is meant by resolution of an instrument
A. Explain the difference between procision and
accuracy of a measurment.
B. During experiment to find the stiffness constant of a
spring, the following graph was obtained. By comparing
the theoretical equation to that of a straight line y=mx+c find the string constant.

The force that causes fluid pressure to vary with depth is the weight of the fluid. As the fluid is a form of matter, it has weight and it exerts a force due to its weight. This force is known as hydrostatic force or pressure.

When the fluid is at rest, the weight of the fluid acts vertically downwards and it exerts pressure on the bottom of the container or on any object submerged in it. The deeper the object is, the more fluid is above it, and the greater the weight of the fluid is, so the greater the pressure is.

This happens because of the concept of Archimedes' principle which states that the buoyant force acting on an object submerged in a fluid is equal to the weight of the fluid that the object displaces. So the deeper an object is submerged in a fluid, the more fluid it displaces, and the greater the buoyant force is. This buoyant force also known as the upthrust is what opposes the weight of the fluid and causes the pressure to vary with depth.

Answer:

129.95 N

Explanation:

First, you want to find the acceleration due to gravity on this hypothetical planet.

Using the equation [tex]g = G (M/R^2)[/tex] , where G is a constant ([tex]6.67 * 10^{-11}[/tex]),  M is mass of the planet, and R is radius of the planet, we can plug in the numbers of earth and then multiply them by whatever the question requires, in this case, 5x.

[tex]g = (6.67 * 10^{-11})(5*(5.97 * 10^{24})) /(5* (6.378 *10^{6}))^{2}[/tex]

g = 1.96 m/s. The acceleration due to gravity on this planet is 1.96 m/s.

Now to find your weight.

First, you want to find your mass.

On earth, your weight is equal to your natural force (Fn)

mg = Fn

m(9.8) = 650 ==> mass = 66.33 kg

Now, to find your weight on this hypothetical planet, multiply your mass by the acceleration due to gravity (g)

M x g

66.33 x 1.96 = 129.95 N

You would weigh 129.95 N

During  Physical Changes,  kinetic energy and thermal energy. of the material changes as well as temperature of the substances also changes.

Physical changes are those that affect a chemical substance's form but not its chemical content. Physical changes may normally be used to separate compounds into chemical elements or simpler compounds, but they cannot be used to separate mixtures into their component compounds.

When something changes physically but not chemically, it is said to have undergone a physical change. Physical means can be used to undo a physical alteration.

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It will take approximately 8 years for a radioactive substance of mass 800g to have 8g undecayed.

The half-life of the radioactive substance in question is 4 years. The half-life of a radioactive substance is the amount of time it takes for half of the original amount of the substance to decay. In this case, after 4 years, half of the initial 800g of the radioactive substance will have decayed, leaving 400g remaining. This means that the decay rate of the radioactive substance is 50% per 4 years. The half-life is a constant for a specific radioactive substance and it does not change, this means that if we wait another 4 years, half of the remaining 400g will decay leaving only 200g, and so on.

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In a position-time graph, we plot the position of an object or a person against elapsed time. The person's position is the distance from the reference point. The shape of the graph shows the kind of motion.

A position-time graph is a type of graph used to represent the motion of an object over time. It plots the position of an object on the y-axis and the time elapsed on the x-axis. The position is usually represented as a distance from a reference point, such as the origin of a coordinate system.

The shape of the graph can provide insight into the nature of the object's motion. For example, a straight line on the position-time graph indicates that the object is moving at a constant velocity. A parabolic shape of the graph shows that the object is accelerating, and a curved line on the graph shows that the object is moving at a non-constant velocity.

It's a powerful tool to understand the motion of an object and its dynamics, it allows you to see the relationship between position, velocity and acceleration, and how they change over time.

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Answer:

below

Explanation:

You will need this equation:

F = G m1 m2 / r^2     G = gravitational constant = 6.6743 x10^-11 m^3/(kg s^2)

Plugging in the values

     6.6743 x 10^-11   *   3.3 * 3.3 / ( .33^2) = 6.67 x 10 ^-9 N

Hydraulic machines work based on the principle of Pascal's Law, which states that the pressure exerted on a confined fluid is transmitted equally in all directions. This means that the pressure applied to one part of a confined fluid is transmitted throughout the entire fluid, regardless of the shape or size of the container. This principle is used in hydraulic machines to transfer force from one point to another by using a fluid, usually oil or water, in a closed system of pipes or cylinders.

The force applied to the small piston of a hydraulic machine is transmitted through the fluid, and it is amplified on the larger piston due to the difference in area between the two pistons. This allows a small force to be amplified into a much larger force, making the machine able to lift or move heavy loads with minimal effort.

This is the basic principle that makes hydraulic systems, such as car brakes, lift, cranes, excavators, and many other machines work.

The number of revolutions the tire makes in 6 s is

N = (58π)/(12π) = 4.83 rev.

What is revolutions?

Revolutions min physics is the study of the physical aspects of revolutions, including the forces and motions that cause them, the structures and systems that are produced in their wake, and the physical processes that lead to their initiation and termination. It has roots in the study of revolutions in the social sciences, but has developed its own principles and techniques to study physical phenomena related to revolutions. These techniques include the use of mathematical models, experiments, numerical simulations, and computer visualizations.

The linear velocity of a point on the tire's circumference is given by

v = (dπ)/t

where d is the diameter of the tire and t is the time.

Substituting d = 58 cm and t = 6 s, the linear velocity of a point on the tire's circumference is

v = (58π)/6 m/s.

The number of revolutions the tire makes in 6 s is given by

N = (v/2π)

Substituting v = (58π)/6 m/s, the number of revolutions the tire makes in 6 s is

N = (58π)/(12π) = 4.83 rev.

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Answer:

see below

Explanation:

Microgravity is a condition in which the gravitational force experienced by an object is very weak. It is characterized by a very small gravitational acceleration, typically less than one thousandth of that experienced on Earth's surface. The gravitational force experienced in microgravity is so small that it is often neglected in many physical phenomena.

A condition under which microgravity can be produced is by placing an object in a state of freefall. Freefall is the state in which an object is falling under the influence of gravity, but it is not in contact with a solid surface. When an object is in freefall, it experiences a condition of weightlessness, which is similar to microgravity.

One of the ways to produce microgravity is by being in orbit around the Earth, at an altitude of around 200 miles or more, the gravitational pull is weak enough to be considered as microgravity. This can be achieved by using spacecrafts or high-altitude balloons, where the object is in a state of free fall around the Earth, and it experiences microgravity.

Another way to achieve microgravity is by using aircrafts, such as the "vomit comet" that flies in parabolic trajectory, allowing the passengers to experience weightlessness for a few minutes during the flight.

If speed of the car is doubled to 28 m/s, the kinetic energy of it will be four times.

The energy an object has as a result of motion is known as kinetic energy in physics. It is described as the effort required to move a mass-determined body from rest to the indicated velocity. The body holds onto the kinetic energy it acquired during its acceleration until its speed changes.

Kinetic energy is directly proportional to square of the speed of the object.

Hence, if its speed is doubled to 28 m/s, the kinetic energy of it will be four times.

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Answer:

C

Explanation:

The system pressure will be equal to 70 pounds divided by the area of the small piston, which is 5.33 square inches. This gives a pressure of 13.13 psi (pounds per square inch).

The work done by the boy against the gravitational force is 240000J.

Here given that,

Mass of the box (m) = 300 g

Height of table (h) = 80cm

Acceleration due to gravity (g) = 10 m/s²

Work done against gravitational force will be calculated by formula,

W = mgh

By substituting the values,

   = 300 x 10 x 80

   = 240000J

Therefore the work done by the boy is 240000J.

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Answer:

Explanation:

In order to determine how far you will have gone after 1.00 min, we need to calculate the distance traveled while coasting down the hill and the distance traveled while pedaling.

To calculate the distance traveled while coasting down the hill, we can use the equation:

distance = initial velocity * time + (1/2) * acceleration * time^2

Since you start at the top of the hill with an initial velocity of 0 m/s, and we know that the acceleration is 2.00 m/s^2, and time is unknown. we can solve for time using the final velocity equation:

velocity = acceleration * time + initial velocity

18 = 2*t + 0

t = 9 sec

Now we have time and acceleration, we can calculate distance.

distance = 0 * 9 + (1/2) * 2 * 9^2

distance = 81 m

Now we know how far you have traveled while coasting down the hill, we can calculate the distance traveled while pedaling.

We know that you are pedaling to maintain a constant speed of 18.0 m/s for 1.00 min, so we can use the formula:

distance = speed * time

distance = 18 * 1*60 = 1080 m

Therefore, in total, you have traveled 1080 + 81 = 1161 m from the time you left the hilltop.

The minimum velocity for the meteorite before entrance into earth's atmosphere is 36.8 m/s.

To calculate the minimum velocity the meteorite must have had before it entered Earth's atmosphere, the equation for heat transfer is:

Q = mcΔT

Where Q = the heat transferred,

m = the mass of the meteorite,

c = the specific heat capacity of iron, and

ΔT = the change in temperature.

The specific heat capacity of iron is approximately = 0.45 J/g°C.

Temperature of the meteorite changes from -105°C to the melting point of iron, which is approximately = 1535°C.

So: Q = mc(1535 - (-105))

Mass of the meteorite unknown, but we know it is made of iron, so assume a value for the mass, such as 100 g.

Q = 100 x 0.45(1535 - (-105))

Solving for Q:

Q = 67875 J

To calculate the kinetic energy of the meteorite, which is given by the equation: Ek = 1/2mv²

where Ek is kinetic energy,

m = the mass of the meteorite and

v = the velocity of the meteorite.

Therefore, the velocity of the meteorite is given by the following equation: v = √(2Ek/m)

Substituting the values of Ek and m, we get

v = √(2 x 67875/100)

Solving for v:

v = √1357.5

The minimum velocity the meteorite must have had before it entered Earth's atmosphere is approximately 36.8 m/s.

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Mass.

Mass, in physics, quantitative measure of inertia, a fundamental property of all matter. It is, in effect, the resistance that a body of matter offers to a change in its speed or position upon the application of a force. The greater the mass of a body, the smaller the change produced by an applied force.

According to the question of forces, the resultant a will be 28N.

What is resultant?
Resultant is a term that is used to describe the combined effect of two or more forces acting on an object. It is the vector sum of the individual forces. Resultant force is the single force that replaces the action of several forces acting on a body. Calculating the resultant force of multiple forces can be done by using the components of the forces in the x and y directions, then using basic vector addition to calculate the resultant force. The resultant force is the combination of the individual forces and the magnitude and direction of the resultant force is determined by the direction and magnitude of the individual forces.

The resultant force of the two forces is equal to the square root of the sum of the squares of the magnitudes of the two forces.

Therefore, the resultant force is equal to √(12^2 + 24^2) = 28 N.

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Answer:

Explanation:

1. Place a cup of hot tea on a flat surface.

2. Place a thermometer in the tea and record the temperature.

3. Place a fan in front of the cup of tea and turn it on.

4. Place the thermometer in the tea again and record the temperature.

5. Compare the two temperatures and observe the difference.

6. The difference in temperature is an indication of the thermal energy that has been dissipated from the cup of hot tea.

The velocity of an object dropped off a cliff can be calculated using the equation:

v = v0 + at

Given:

v0 = 0 m/s (initial velocity)

a = -9.8 m/s^2 (acceleration due to gravity)

At the end of 2 seconds:

t = 2 s

v = v0 + at = 0 m/s + (-9.8 m/s^2) * 2 s = -19.6 m/s

The velocity of the object at the end of 2 seconds is -19.6 m/s, downward.

At the end of 5 seconds:

t = 5 s

v = v0 + at = 0 m/s + (-9.8 m/s^2) * 5 s = -49 m/s

The velocity of the object at the end of 5 seconds is -49 m/s, downward.

At the end of 12 seconds:

t = 12 s

v = v0 + at = 0 m/s + (-9.8 m/s^2) * 12 s = -117.6 m/s

The velocity of the object at the end of 12 seconds is -117.6 m/s, downward.

It's worth mentioning that in the case of an object falling freely under the influence of gravity alone, the velocity will continue to increase

Atoms are typically spaced about 0.2 nm apart, which means that there are 5 nm in 1 micrometer (1nm = 0.001 micrometer).

To convert inches to micrometres we can use the conversion factor 1 inch = 25.4 micrometres.

So 4.97 inches is equal to 4.97 x 25.4 = 126.988 micrometres

And if we divide 126.988 micrometres by 5 micrometres we get 25.3976

So, there would be 25 atoms in a line 4.97 inches long.

The dimensional relation of the time period bob with its length is shown below.

a method of analysis that represents physical quantities in terms of their fundamental dimensions in the absence of enough data to create precise equations.

Dimensional analysis is a method used in engineering and the physical sciences to reduce physical quantities like acceleration, viscosity, and energy to their three basic dimensions of length, mass, and time (T).

[T]=[M^0 L^0 T^1]

[L]=[M^0 L^1 T^0]

[g]=[M^0 L^1 T^-2]

SQUARE ROOT OF (L/g)=[m0l1t0]/[m0l1t-2]

                                         =[m0l0t1]

                                            = R.H.S.

Hence it's dimensionally correct.

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If we observe the skies from the surface of another planet, we can see  heliocentric solar system, that is, all the planets are rotating around the sun.

The Heliocentric model is an astronomy theory that places the Sun at the centre of the cosmos, with the Earth and other planets revolving around it. In the past, geocentrism, which put the Earth at its center, was countered by heliocentrism.

Aristarchus of Samos first offered the idea that the Earth revolves around the Sun in the third century BC after being influenced by a theory put forth by Philolaus of Croton (c. 470 – 385 BC).

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Answer:V(t)=20t^2-100t+50t

as we know accl means derivatives of velocity.

a/q,

dv/dt =0

dv/dt=20t^2-100t+50t=0

dv/dt=4t-100+50=0

=>40t-50=0

=>40t=50

=>t=1.25

therfore Vs= 20t^2-100t+50t

Vs=20(1.25625)-125+62.5

Vs=31.25-125+62.5

Vs=-31.25

Answer:

The tension in [tex]T_1[/tex] is 0.1024 Newtons.

The tension in [tex]T_2[/tex] is 0.1157 Newtons.

Explanation:

Lets create a free body diagram showing all of the forces; we need to show the vertical and horizontal components of the tension.

I will attach a picture of my free body diagram. Notice I created 2 new triangles with the adjacent angles of angle A and C from the original picture.

Lets make a list of all the variables we have now. Also lets write down the information we are given.

[tex]A=27\\C=38\\m=12\\g=9.81\\W\\T_{1} \\T_{1x} \\T_{1y}\\T_{2} \\T_{2x} \\T_{2y} \\[/tex]

In this situation the sum of of the vertical tension components must support the weight. To find the vertical components we can use the SIN function.

[tex]sin(x)=\frac{O}{H} \\O=Hsin(x)[/tex]

Therefore we can write that the sum of the forces in the y direction is

[tex]\sum F_y=T_1sin(A)+T_2sin(C)=W[/tex]

This system is in equilibrium; the object should not move along the x-axis. Therefore, the horizontal components of [tex]T_1[/tex] and [tex]T_2[/tex] must then equal each other. To find the horizontal components we can use the COS function.

[tex]cos(x)=\frac{A}{H} \\A=Hcos(x)[/tex]

Therefore we can write that the sum of the forces in the x direction is

[tex]\sum F_x=T_1cos(A)=T_2cos(C)[/tex]

Now we have to equations to help us solve the problem.

[tex]T_1cos(A)=T_2cos(C)[/tex]

[tex]T_1sin(A)+T_2sin(C)=W[/tex]

We do not know the numerical values of [tex]T_1[/tex] and [tex]T_2[/tex] so we will have to manipulate algebraically to solve them.

In the first equation lets solve for [tex]T_1[/tex].

[tex]T_1cos(A)=T_2cos(C)[/tex]

Divide both sides by [tex]cos(A)[/tex].

[tex]T_1=\frac{T_2cos(C)}{cos(A)}[/tex]

Separate the right side into two fractions.

[tex]T_1=\frac{T_2}{1} *\frac{cos(C)}{cos(A)}[/tex]

Use the reciprocal trig identity for cosine.

[tex]sec(x)=\frac{1}{cos(x)}[/tex]

[tex]T_1=\frac{T_2}{1} *cos(C)}*sec(A)[/tex]

[tex]T_1=T_2*cos(C)}*sec(A)[/tex]

Now insert our answer for [tex]T_1[/tex] into the second equation.

[tex]T_2*cos(C)}*sec(A)*sin(A)+T_2*sin(C)=W[/tex]

Solve for [tex]T_2[/tex]. Lets replace each trig function with its own variable to make this easier.

[tex]T_2*cos(C)}*sec(A)*sin(A)+T_2*sin(C)=W[/tex]

[tex]cos(C)=x\\sec(A)=y\\sin(A)=z\\sin(C)=u[/tex]

[tex]T_2*x*y*z+T_2*u=W\\T_2xyz+T_2u=W[/tex]

Now lets solve for [tex]T_2[/tex].

Factor [tex]T_2[/tex] out of each term.

[tex]T_2(xyz)+T_2(u)=W[/tex]

Factor [tex]T_2[/tex] out of each term.

[tex]T_2(xyz+u)=W[/tex]

Divide each side by [tex]xyz+u[/tex].

[tex]T_2=\frac{W}{xyz+u}[/tex]

Lets substitute the trig functions back in for the variables

[tex]T_2=\frac{W}{cos(C)*sec(A)*sin(A)+sin(C)}[/tex]

[tex]W[/tex] is the weight.

The formula for weight is [tex]W=mg[/tex]. Where [tex]m[/tex] is the mass in kilograms.

12 grams is 0.012 kilograms.

[tex]W=0.012*9.81[/tex]

[tex]W=0.11772[/tex]

Numerical Evaluation

Lets evaluate [tex]T_2[/tex].

[tex]T_2=\frac{0.11772}{cos(38)*sec(27)*sin(27)+sin(38)}[/tex]

[tex]T_2=0.11573[/tex]

Lets evaluate [tex]T_1[/tex].

[tex]T_1cos(A)=T_2cos(C)[/tex]

[tex]T_1*cos(27)=0.11573*cos(38)\\T_1=0.10235443[/tex]

A rating/review would be much appreciated.

Answer:

T₁ = 102.25 N (2 d.p.)

T₂ = 115.61 N (2 d.p.)

Explanation:

The diagram shows a body of mass 12 kg (weight = 12g N) held in equilibrium by two light, inextensible strings. One string makes an angle of 27° with the positive horizontal and the other string makes an angle of 38° with the negative horizontal.

The body is in equilibrium, so both the horizontal and vertical components of the forces must sum to zero.

Resolving horizontally, taking (→) as positive:

[tex]\implies -T_1 \cos (27^{\circ})+T_2 \cos (38^{\circ})=0[/tex]

[tex]\implies T_1 \cos (27^{\circ})=T_2 \cos (38^{\circ})[/tex]

[tex]\implies T_1=\dfrac{T_2 \cos (38^{\circ})}{ \cos (27^{\circ})}[/tex]

Resolving vertically, taking (↑) as positive:

[tex]\implies T_1 \sin(27^{\circ})+T_2 \sin(38^{\circ})-12\text{g}=0[/tex]

[tex]\implies T_1 \sin(27^{\circ})+T_2 \sin(38^{\circ})=12\text{g}[/tex]

Substitute the found expression for T₁ into the second equation and take g = 9.8 ms⁻²:

[tex]\implies \left(\dfrac{T_2 \cos (38^{\circ})}{ \cos (27^{\circ})}\right) \sin(27^{\circ})+T_2 \sin(38^{\circ})=12\text{g}[/tex]

[tex]\implies T_2 \cos (38^{\circ})\tan(27^{\circ})+T_2 \sin(38^{\circ})=12\text{g}[/tex]

[tex]\implies T_2 \left(\cos (38^{\circ})\tan(27^{\circ})+ \sin(38^{\circ})\right)=12\text{g}[/tex]

[tex]\implies T_2 =\dfrac{12\text{g}}{\cos (38^{\circ})\tan(27^{\circ})+ \sin(38^{\circ})}[/tex]

[tex]\implies T_2=115.614550...\:\text{N}[/tex]

Substitute the found value of T₂ into the equation for T₁ and take g = 9.8 ms⁻²:

[tex]\implies T_1=\dfrac{\left(\dfrac{12\text{g}}{\cos (38^{\circ})\tan(27^{\circ})+ \sin(38^{\circ})}\right) \cos (38^{\circ})}{ \cos (27^{\circ})}[/tex]

[tex]\implies T_1=102.250103...\text{N}[/tex]

Therefore, the value of T₁ and T₂ in the given diagram is:

The most powerful ice breaker can work 2.016 × 10 ¹¹ Joule in 1.0 hour.

The quantity of energy moved or converted per unit of time is known as power in physics. The watt, or one joule per second, is the unit of power in the International System of Units. Power is also referred to as activity in ancient writings. A scalar quantity is power.

Power of the nuclear engine = 56 × 10⁶ W.

Time it works = 1 hour = 3600 second

Hence, work done by  this engine  in 1.0 hour =  56 × 10⁶ × 3600 Joule

= 2.016 × 10 ¹¹ Joule.

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The year that the CO level exceed the permissible limit is C. 2019

In the US, the permissible exposure limit is the maximum level of exposure to a chemical substance or physical agent, such as high levels of noise. The Occupational Safety and Health Administration establishes permissible exposure limits.

The maximum level of a substance to which a person can be exposed is known as the permissible exposure limit (PEL). When carbon monoxide levels in your bloodstream rise, carbon monoxide poisoning happens. Your body replaces the oxygen in your red blood cells with carbon monoxide when there is too much carbon monoxide in the air. Serious tissue damage or even death may result from this.

When gasoline, wood, propane, charcoal, or other fuels are burned, carbon monoxide, an odorless, tasteless gas, results. Appliances and engines that aren't properly ventilated, especially in a room that's tightly sealed or enclosed, can build up dangerous amounts of carbon monoxide.

In this case, the appropriate year is 2019.

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The magnitude of the resultant moment exerted at O, for the configuration given in the Figure is 0.63 Nm.

The magnitude of the resultant displacement of the object is calculated by applying the formula of Pythagoras theorem as shown below.

d = √ (dx² + dy² )

where;

d = √ (0.05² + 0.15² )

d = 0.158 m

The magnitude of the resultant moment exerted at O, for the configuration given in the Figure is calculated by applying the formula for torque or moment.

τ = Fd

where;

τ = ( 4 N ) x ( 0.158 m )

τ = 0.63 Nm

Thus, the resultant moment is a function of the applied force and the resultant displacement.

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The correct description of X is that it is a neutron (option C).

A nuclear reaction is a process such as the fission of an atomic nucleus, or the fusion of one or more atomic nuclei and/or subatomic particles in which the number of protons and/or neutrons in a nucleus changes.

In a nuclear reaction, the reaction products may contain a different element or a different isotope of the same element.

Certain particles are emitted or reacted with in a nuclear reaction. Examples of those particles are neutron, alpha particle, electron.

A neutron is a subatomic particle forming part of the nucleus of an atom and having no charge. A neutron posseses a mass number of 1 and atomic number of 0.

According to this question, uranium with mass number 235 and atomic number 92 undergoes a nuclear reaction with a particle with mass number 1 and atomic number 0.

The particle represented by X in this reaction is a neutron.

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Answer:

no I can’t help you

Explanation:

I can’t help you because I don’t know the answer

Answer:

Explanation:

R = (50 ohms x 5A) / 1mA = 250 ohms

The resistance of the resistor is 250 ohms.

The resistivity (ρ) = 2 x 10^-6 cm^2

The cross-sectional area (A) = 4 x 10^-4 cm^2

Therefore, the length (l) = (ρ x R) / A

l = (2 x 10^-6 cm^2 x 250 ohms) / (4 x 10^-4 cm^2)

l = 1.25 cm