A metal wire, fixed at one end, has length l and cross-sectional area A. The wire extends a distance e which mass m is hung from the other end of the wire.What is an expression for the Young Modulus E of the metal?

A big tractor is more efficient and productive than a small tractor, allowing it to plow through more fields and cover more ground with less time and effort.

Engine Power: Big tractors have larger and more powerful engines than small tractors, which allow them to generate more torque and power to pull heavy loads and work for longer periods of time without overheating or breaking down. This means they can work more efficiently and cover more ground than small tractors.

Size and Weight: Big tractors are usually larger and heavier than small tractors, which gives them more stability and traction on the ground. This allows them to plow through tough and uneven terrain with less effort and more control, reducing the time and effort needed to complete the task.

Implements: Big tractors can accommodate larger and more advanced implements, such as wider plows, cultivators, and seeders, which allow them to cover more ground with each pass. These implements can also be customized to match the specific needs of the soil and crops, increasing the efficiency and productivity of the tractor.

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Answer:

You can use the same conversion factor to convert liters to gallons or you can use: 1 liter = 0.264 US gallons. To find how many gallons are in 4 liters, for example: gallons = 4 liters x 0.264 gallons/liter. The liters cancel out, leaving the gallon unit: 4 liters = 1.056 gallons. Keep this in mind: there are about 4 liters per US gallon.

Explanation:

Answer:

Explanation:

Angular momentum of an object is given by L = Iω, where I is the moment of inertia and ω is the angular velocity.

To find the angular momentum of the car, we need to first find its moment of inertia about the axis of rotation (which in this case is the center of the curve).

The moment of inertia of a point mass m rotating around an axis at a distance r is given by I = mr^2.

The car can be thought of as a collection of point masses, so we need to integrate the moment of inertia of each point mass over the entire car.

Assuming the car is a uniform rectangular box with dimensions 4.5 m x 1.8 m x 1.5 m, we can divide it into smaller cubes of mass dm and volume dV. The moment of inertia of each cube is given by dI = dm(r^2), where r is the distance from the cube to the axis of rotation.

Integrating over the entire car, we get:

I = ∫(dm)(r^2) = ∫(ρdV)(r^2)

where ρ is the density of the car.

The volume of the car is V = (4.5 m)(1.8 m)(1.5 m) = 12.15 m^3, and assuming a density of 1000 kg/m^3 (typical for cars), the mass of the car is m = (1000 kg/m^3)(12.15 m^3) = 12150 kg.

We can express the distance r as the sum of the radius of the curve (120 m) and the distance between the center of mass of the car and the pivot point (which we can approximate as half the length of the car, or 0.75 m).

So, r = 120 m + 0.75 m = 120.75 m.

Substituting these values into the equation for I, we get:

I = ∫(ρdV)(r^2) = ρ∫dV(r^2) = ρV(r^2) = (1000 kg/m^3)(12.15 m^3)(120.75 m)^2 = 1.796 x 10^7 kg·m^2

To find the angular velocity of the car, we can use the formula v = ωr, where v is the linear velocity of the car and ω is the angular velocity.

The linear velocity of the car is given by v = 21 m/s, and the radius of the curve is 120 m. So,

ω = v/r = (21 m/s)/(120 m) = 0.175 rad/s

Finally, we can find the angular momentum of the car by multiplying the moment of inertia by the angular velocity:

L = Iω = (1.796 x 10^7 kg·m^2)(0.175 rad/s) = 3.145 x 10^6 kg·m^2/s

Therefore, the angular momentum of the car is 3.145 x 10^6 kg·m^2/s.

The angular momentum of the car in the given example is [tex]3,780,000 kg m^2/s.[/tex]

The amount of rotational motion an object has around a certain axis is measured by its angular momentum. It is the result of an object's angular velocity and moment of inertia. It is a vector quantity with a direction and magnitude.

We need to apply the following calculation to determine the car's angular momentum:

L = I * ω

where L is angular momentum, I is the moment of inertia, and ω is the angular velocity.

We must apply the following formula to determine the moment of inertia:

[tex]I = m * r^2[/tex]

where r is the curve's radius and m is the car's mass.

m = 1500 kg r = 120 m

[tex]I = m * r^2[/tex]

[tex]I = 1500 kg * (120 m)^2\\I = 21,600,000 kg m^2[/tex]

The following formula must be used to determine the angular velocity:

v = ω * r

where v denotes the car's speed.

v = 21 m/s r = 120 m

where,

v/r = 21 m/s/120 m = 0.175 rad/s

We can now determine the angular momentum:

L = I * ω

[tex]L = 21,600,000 kg m^2 * 0.175 rad/s\\L = 3,780,000 kg m^2/s[/tex]

Therefore, the angular momentum of the car is [tex]3,780,000 kg m^2/s.[/tex]

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There is likely to be eutrophication in the water

There are less turbid substances deposited in the water within the time.

The decrease of water grasses means the primary productivity reduced.

An increase in nitrogen and phosphorus content in Chesapeake Bay can have significant environmental impacts. Chesapeake Bay is an estuary that is highly sensitive to nutrient pollution, which can cause the growth of harmful algal blooms and oxygen depletion in the water.

When excess nitrogen and phosphorus from fertilizers, animal waste, and sewage enter the Bay, they can cause an overgrowth of algae. As these algae die and decompose, they consume oxygen in the water, leading to low oxygen conditions known as "hypoxia" or "dead zones". This can harm fish, shellfish, and other aquatic life, and can also have economic impacts on the fishing and tourism industries.

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Jason weighs 150 N and sits on his big brother's shoulders. Big brother weighs 400 N. the support force supplied by the floor must be 500N.

Force can be defined as any influence that causes an object to undergo a change in motion, direction, or shape. In physics, force is represented as a vector quantity, which means it has both magnitude and direction. The standard unit of force is the newton, which is defined as the force required to accelerate a mass of one kilogram at a rate of one meter per second squared.

Force can be categorized into two types: contact force and non-contact force. Contact force is a force that is exerted through direct contact between two objects, while non-contact force is a force that is exerted without any physical contact between two objects, such as gravity or electromagnetic force. Force plays a crucial role in the study of physics, as it governs the behavior of all objects in the universe.

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Complete Question:-

Jason weighs 150 N and sits on his big brother's shoulders. Big brother weighs 400 N. the support force supplied by the floor must be

Astronomers believe that the reason for the low levels of hydrogen and helium in the inner part of the Solar System is that these elements were lost due to the Sun's strong solar wind

. Most of the gas in the solar nebula was hydrogen and helium. However, there is very little hydrogen or helium in the inner part of the solar system today. Astronomers believe this is because the intense solar winds from the young Sun blew the lighter gases out into space.

The solar winds also blew away any smaller particles that had not yet stuck together to form larger objects, which is why there are very few small objects close to the Sun. This is why there is more hydrogen and helium in the outer part of the solar system.

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потенциальная енергия - E=mgh, g = ускорение свободного падения, всегда равна 9.81, примерно 10: g=10. Единица измерения енергии - Джоул: [E] = Дж

от этого, E=15×10×6=900 J

ответ: 900 Дж

The number and wattage of lamps required to illuminate the workshop would be approximately 8 lamps and 70 watts respectively.

To estimate the number and wattage of lamps required to illuminate a workshop space of 60x1.5 meters, we can follow these steps:

Calculate the area of the workshop:

Determine the total lumens required:

Adjust for the coefficient of utilization and luminous efficiency:

Adjust for space-height ratio and candle power depreciation:

Determine the number of lamps required:

Determine the wattage of each lamp:

Therefore, approximately 8 lamps with a wattage of 70 watts each would be required to illuminate the workshop space.

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Sam traveled a total distance of 60 miles, but his displacement is zero, as he ended up back at his starting point after all of his movements.

How to measure the distance?

The distance that Sam has traveled is the total length of the path he took, regardless of the direction. In this case, the distance can be calculated as follows:

Distance = 20 miles (North) + 10 miles (East) + 20 miles (South) + 10 miles (West)

Distance = 60 miles

Therefore, Sam has traveled a total of 60 miles.

The displacement, on the other hand, is the shortest distance between the starting point and the ending point. It is the distance between the initial and final position of an object, measured in a straight line. To calculate the displacement, we need to find the net vector sum of all the individual movements.

Starting from the origin, Sam moved 20 miles to the north and then 20 miles to the south, which means he ended up back at the starting point. Next, he moved 10 miles to the east and then 10 miles to the west, which also means he ended up back at the starting point.

Therefore, the displacement of Sam's journey is zero.

In summary, Sam traveled a total distance of 60 miles, but his displacement is zero, as he ended up back at his starting point after all of his movements.

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To solve for the current I3 in wire 3, we can apply the principle of conservation of charge, which states that the total current flowing into a junction must equal the total current flowing out of the junction. This can be expressed mathematically as:

I1 + I2 = I3

where I1 and I2 are the currents in wires 1 and 2, respectively, and I3 is the current in wire 3.

To find I1 and I2, we can use the formulas for current (I = J x A), where J is the current density and A is the cross-sectional area of the wire. The cross-sectional area can be calculated from the diameter using the formula A = π/4 x d^2, where d is the diameter.

For wire 1:

I1 = J1 x A1 = 2.1 A/mm^2 x π/4 x (1.7 mm)^2 = 4.52 A

For wire 2:

I2 = J2 x A2 = 3.9 A/mm^2 x π/4 x (2.4 mm)^2 = 13.21 A

Substituting these values into the conservation of charge equation, we get:

4.52 A + 13.21 A = I3

Simplifying, we get:

I3 = 17.73 A

Therefore, the current I3 in wire 3 is approximately 17.73 amperes (or amps) to two significant figures.

Current can be thought of as the rate at which electric charges flow through a circuit. It is caused by the movement of electrons, which are negatively charged particles, in response to an electric field. In a metallic conductor, such as a wire, electrons can move freely through the material, which allows current to flow easily.

Current can be either direct current (DC) or alternating current (AC). DC flows in one direction, whereas AC changes direction periodically. DC is commonly used in batteries and electronic devices, while AC is used for power transmission over long distances.

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a. Here is a diagram of the situation:

                Q (-40 pC)

       |

       |

       |    (0,3)

       |

------ o-------- x-axis

       |

       |

       |    (0,0)

       |

     q (50 pC)

(b) The net electric flux through the closed cylindrical surface is -5.69×10⁵ Nm²/C.

To calculate this, we use Gauss's Law, which states that the net electric flux through any closed surface is proportional to the net charge enclosed by the surface. Mathematically, this is expressed as:

flux = E * A = (q_enclosed / ε0) * A

where E is the electric field, A is the area of the closed surface, q_enclosed is the net charge enclosed by the surface, and ε0 is the permittivity of free space.

In this case, we have a cylindrical surface with a height of 4 m and a diameter of 5 mA (which means a radius of 2.5 mA). The cylinder is centered at the origin and has the z-axis as its axis of symmetry. To apply Gauss's Law, we need to find the net charge enclosed by the cylinder.

Both charges q and Q are on the x-y plane, so they do not contribute to the net charge enclosed by the cylindrical surface. Therefore, the net charge enclosed by the surface is simply the sum of q and Q:

q_enclosed = q + Q = (50 pC) + (-40 pC) = 10 pC

Substituting this into Gauss's Law, we get:

flux = (q_enclosed / ε0) * A = (10 pC / 8.85×10⁻¹² F/m) * π (2.5×10⁻³ m)² (4 m) = -5.69×10⁵ Nm²/C

Therefore, the net electric flux through the closed cylindrical surface is -5.69×10⁵ Nm²/C.

What is an electric flux?

Electric flux is the measure of the number of electric field lines passing through a given surface. It is a scalar quantity and represents the amount of electric field passing through a surface per unit area. The SI unit of electric flux is volt-meter (V m) or newton-meter squared per coulomb (N m2/C).

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Option B, C, D, E, and G: The chemical makeup of star-forming clouds is identical to that of the galaxy as a whole and the majority of the hydrogen in clouds that generate stars is present as hydrogen molecules (H₂).

Interstellar molecular clouds, which are opaque collections of extremely cold gas and dust, are where stars are formed. When some of those aggregates accumulate enough mass to collapse due to gravity alone, the process begins. The cause could even be as simple as random density changes within the cloud.

The correct statements are:

The chemical makeup of star-forming clouds is identical to that of the galaxy as a whole.

The majority of the hydrogen in clouds that create stars is present as hydrogen molecules (H₂).

The interstellar dust particles that make up these clouds' visual blackness absorb the majority of light.

Even though the densest cloud regions appear dark to telescopes using visible light, we can see inside them using infrared telescopes.

A region where the gas is heated by radiation from neighboring stars is where star-forming clouds are found.

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Answer:

If frequency is constant, wavelength will get longer as speed increases. Here is an animation of a wave changing speed. The green dots and line show that frequency is constant on both mediums, but the speed and wavelength both change.

Here ya go! i think this will help!

The subtle gradation of light and shadow to create the effect of three-dimensionality is described as shading.

In the context of art, shading refers to the use of light and shadow to render a three-dimensional object or scene realistically.

When an object is illuminated, light falls on its surface in different ways, depending on the position of the light source, the object's orientation, and the object's shape.

In this way, shadows are formed on the object's surface, and some regions receive more or less light than others.

By accurately depicting these light and shadow areas, artists can create an illusion of depth and dimensionality in their works.

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Answer:

check

Explanation:

When you contact anything hot, the heat is transmitted from the object to your hand, making it feel hot. When you contact something cold, heat is transmitted from your hand to the object, making it feel chilly.

when heated, the molecules of the liquid in the thermometer move faster, causing them to get a little further apart. this results in movement up the thermometer. when cooled, the molecules of the liquid in the thermometer move slower, causing them to get a little closer together.

When the liquid in the thermometer is heated, the molecules move quicker, forcing them to move wider apart. This causes the thermometer to rise. When the liquid in the thermometer is chilled, the molecules travel slower, leading them to get closer together.

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The angle between the polarization direction of the second film and the vertical direction should be approximately 51.4° so that 37.5% of the original light intensity reaches the detector.

Let's denote the angle between the vertical polarization direction of the first film and the polarization direction of the second film by θ. The transmitted intensity of the light after passing through the two films is given by Malus's law:

I = I₀ cos²θ

where I₀ is the initial intensity of the unpolarized light.

We want to find the angle θ that will result in 37.5% of the original light intensity reaching the detector. This means that we want to solve the equation:

I/I₀ = 0.375

Substituting the expression for I into this equation, we get:

cos²θ = 0.375 / I₀

Taking the square root of both sides and using the fact that cosθ is positive when 0 ≤ θ ≤ π/2, we get:

cosθ = √(0.375 / I₀)

θ = arccos(√(0.375 / I₀))

Now we need to substitute the values of I₀ and evaluate the expression for θ. Let's assume that the intensity of the original light is I₀ = 1 W/m². Then we get:

θ = arccos(√(0.375 / 1)) = arccos(0.6124) = 51.4°

Therefore, the angle between the polarization direction of the second film and the vertical direction should be approximately 51.4° so that 37.5% of the original light intensity reaches the detector.

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Imaging: How big is the Andromeda Galaxy? What are the prime surface features of Mars? Are the stars in the Orion Nebula surrounded by gas?

Spectroscopy: What is the chemical composition of Crab Nebula? Determine the temperature of Jupiter's atmosphere?

Timing: Does the star Mira vary in it's brightness?

Spectroscopy is known to be the study of the absorption and emission of light and other radiation by matter. It is related that these processes depend on the wavelength of the radiation. Recently, the definition has been extended to include the study of interactions between particles like electrons, protons and ions, and interactions with other particles as a function of collision energy.

Spectroscopy has been essential to the development of some of the most fundamental theories of physics, including quantum mechanics, special and general relativity, and quantum electrodynamics. Spectroscopy applied to high-energy collisions has become an important tool in advancing the scientific understanding not only of electromagnetic forces, but also of strong and weak nuclear forces.

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Resistance of wire does not depend on current supplied, area of cross-section of the wire, length of the wire, or material of the wire.

The resistance of a wire does not depend on the current supplied. The resistance of a wire is determined by the following factors:

Length of the wire: The longer the wire, the more resistance it will have. This is due to the fact that a longer wire has more atoms that obstruct the flow of electrons. The more time the electrons take to traverse the wire, the more collisions they will have, resulting in more resistance.

Area of cross-section of the wire: The cross-sectional area of a wire is inversely related to its resistance. This implies that if the cross-sectional area is reduced, the resistance will rise. This is due to the fact that a smaller cross-sectional area leads to more electron collisions with atoms.

Material of the wire: The resistivity of the wire's material determines its resistance. A material with a higher resistivity would have more resistance than one with a lower resistivity. It's important to note that the resistivity of a material varies with temperature. As the temperature rises, so does the resistivity of the substance.

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A. Baterry takes time = 2.9x[tex]10^{8}[/tex] J / power to deplete.

What is time taken?

To determine how long it takes to deplete the battery, we can use the formula:

time = energy / power

where energy is the energy stored in the battery (2.9x[tex]10^{8}[/tex] J) and power is the power delivered by the battery (which we will determine in part B).

time = 2.9x[tex]10^{8}[/tex] J / power

B. Power delivered by the baterry is 20864.5 W

What is the power?

To determine the power delivered by the battery, we can use the formula:

power = energy / time

where energy is the energy stored in the battery (2.9x[tex]10^{8}[/tex] J) and time is the time it takes to deplete the battery (which we will determine in part A).

First, let's convert the distance traveled from kilometers to meters:

402 km = 402,000 m

Now, we can use the formula:

time = distance / speed

where distance is the distance traveled (402,000 m) and speed is the speed of the car (105 km/hr = 29 m/s).

time = 402,000 m / 29 m/s = 13896.6 s

Now we can calculate the power delivered by the battery:

power = 2.9x[tex]10^{8}[/tex] J / 13896.6 s = 20864.5 W

C.  The current delivered by the battery is 52.2 A.

What is current?

The power delivered by the battery is related to the current and potential difference in the circuit by the formula:

power = potential difference x current

The potential difference in the circuit is given as 400 V. Therefore, we can rearrange the formula to solve for the current:

current = power / potential difference

current = 20864.5 W / 400 V = 52.2 A

Therefore, the current delivered by the battery is 52.2 A.

D. We cannot directly determine the resistance of the circuit from the given information.

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Without more specific details, it is difficult to determine exactly what observations might be made if strings are released in a trolley.

However, here are a few general possibilities:

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The voltage reading V,(t) across the resistor at time t after t = 0 is equal to the current I(t) multiplied by the resistance R, since V = IR. Therefore, V,(t) = RI(t).

A resistor is an electrical component that reduces the flow of current in a given circuit. It is made from a conductive material, generally either carbon or metal, that has been treated to produce a specific resistance value. The resistance value of a resistor is measured in ohms, and is generally marked on the component itself. Resistors are used to limit the amount of current flowing through a circuit, which in turn can control the voltage and power levels in the circuit. They can also be used to create voltage dividers which divide the voltage of a circuit into different levels, or to provide stability to a circuit by providing a fixed current. Resistors are a fundamental component of all electronic circuits and are used in a wide range of applications.

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Complete Question:

Explanation:

a) looks correct  EXCEPT   KE and GPE labels are reversed ( if the one on the L is initially and the R one is at max height)

b) looks good

c)  incorrect       total energy will be KE + GPE =   57.51 J at any point

d) correct

The minimum time required to pull out lonie from the snake pit is √(3/4) seconds.

Given: Mass, m = 70 kg Distance, d = 3 m Limiting tension, T = 755N

The minimum time required to pull out lonie from a snake pit, t

Given, mass, m = 70 kg Acceleration due to gravity, g = 9.8 m/s²Distance, d = 3 m

Let's assume the minimum time required to pull out lonie from a snake pit is t.

So, using the equation of motion,S = ut + 1/2 at²

Here, S = d = 3m (Distance),u = 0 m/s (Initial velocity),a = g = 9.8 m/s² (Acceleration) and t = time

Substituting the above values in the equation, we get3 = 0 + 1/2 × 9.8 × t² => t² = 3/4 => t = √(3/4) sec

Also, we know that the tension in the rope is given byT = mg + ma

Now, the rope will break when T exceeds 755 N.

So, substituting the values of m, g, and a in the above equation, we getT = mg + ma = 70 × 9.8 + 70 × a

Since the tension in the rope should be less than or equal to 755 N, we have70 × 9.8 + 70 × a ≤ 755 => a ≤ (755 - 70 × 9.8)/70=> a ≤ 3.29 m/s²

Therefore, the minimum time required to pull out lonie from the snake pit is √(3/4) seconds.

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a. The angular acceleration of the engine is -1320 rad/s².

b. The engine makes approximately 118.7 revolutions during the deceleration.

Given:

Initial angular velocity (ω1) = 4500 rpm

Final angular velocity (ω2) = 1200 rpm

Time is taken (t) = 2.5 s

a) The formula for angular acceleration is:

α = (ω2 - ω1) / t

Substituting the given values, we get:

α = (1200 rpm - 4500 rpm) / 2.5 s = -1320 rad/s² (negative sign indicates a deceleration)

Therefore, the angular acceleration of the engine is -1320 rad/s².

b) To find the total number of revolutions, we need to convert the initial and final angular velocities from rpm to rad/s:

ω1 = 4500 rpm × 2π/60 = 471 rad/s

ω2 = 1200 rpm × 2π/60 = 126 rad/s

The average angular velocity (ω_avg) during the deceleration is given by:

ω_avg = (ω1 + ω2) / 2 = (471 rad/s + 126 rad/s) / 2 = 298.5 rad/s

The total angular displacement (θ) of the engine during the deceleration is given by:

θ = ω_avg × t = 298.5 rad/s × 2.5 s = 746.25 rad

Finally, the total number of revolutions (N) made by the engine is:

N = θ / 2π = 746.25 rad / 2π rad/rev = 118.7 rev (approximately)

Therefore, the engine makes approximately 118.7 revolutions during the deceleration.

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When a ray of light hits a surface, the angles made by the reflection and refraction of the ray must all be measured from the normal, which is perpendicular to the surface at the point where the light ray hits it.

Reflection occurs when light rays hit a surface and bounce back whereas Refraction, occurs when light travels through a medium of a different density or refractive index.

The laws of reflection and refraction states that the angle of incidence is equal to the angle of reflection, and the ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant. This ratio is known as the refractive index of the material from where the light is passing through.

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Answer:

Solve for force:

Ff = UFn

Ff = 0.75(Fn)

Ff = 0.75(1515 + 1225 * g)

Ff = 20550N

Solve for acceleration:

F= ma

20550N = (1515 + 1225) a

a = 7.5m/s^2

solve for time:

a = d / t^2  --->  7.5m/s^2 = 18.5/ t^2  ----> t = 0.85s

solve for velocity final

Impulse = F * t = 20550N * 0.85s

mv^2 = Impulse = 17467.5

(1515 + 1125)v^2 = 17467.5

vf = 2.5m/s

Plug in stuff:

1515 * v1 + 1125 * (-18.3m/s) = (1515 + 1125) * 2.5m/s

v1 = 9.23

Note: I converted 41mph(v2) to 18.3m/s, which is negative because "westward" is in the negative direction.

Explanation: Inelastic collision

Extra: I'm guessing because the two cars slide, the only force acting on them is the force of friction(so it's our net force), hence the Fnet = ma.