A homemade capacitor is assembled by placing two 10-in. pie pans 5 cm apart and connecting them to the opposite terminals of a 9-V battery.
A) Estimate the capacitance.
B) Estimate the charge on each plate.
C) Estimate the electric field halfway between the plates.
D) Estimate the work done by the battery to charge the plates.
E) Which of the above values change if a dielectric is inserted?

The estimated length of the refracting telescope is approximately 412.8 cm.

The magnification (M) of a telescope is given by the formula: M = focal length of the objective lens / focal length of the eyepiece. In this case, the magnification is 85, and the focal length of the eyepiece is 4.8 cm.

Rearranging the formula, we can find the focal length of the objective lens:

focal length of the objective lens = M × focal length of the eyepiece = 85 × 4.8 cm = 408 cm.

Now, to estimate the length of the telescope, we need to consider the formula for the total length of a refracting telescope:

total length = focal length of the objective lens + focal length of the eyepiece.

Substituting the values, we have:

total length = 408 cm + 4.8 cm = 412.8 cm.

Please note that the actual length of a refracting telescope depends on various factors, such as the design, focal lengths, and positioning of the lenses, which may differ from the assumptions made in this response.

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A hydrogen atom in the n=4 state decays to the n=1 state. The wavelength of the photon that the hydrogen atom emits is 97.2 nm.

To calculate the wavelength of the photon emitted when a hydrogen atom transitions from the n=4 state to the n=1 state, we can use the Rydberg formula:

1/λ = R * (1/n₁² - 1/n₂²)

Where:

λ is the wavelength of the photon

R is the Rydberg constant for hydrogen (approximately 1.097 x 10⁷ m⁻¹)

n₁ is the initial energy level (n=4)

n₂ is the final energy level (n=1)

1/λ = 1.097 x 10⁷ m⁻¹ * (1/16 - 1)

1/λ = 1.097 x 10⁷ m⁻¹ * (-15/16)

λ = -0.972×10⁷ m⁻¹

Since wavelength cannot be negative, we take the absolute value

λ ≈ 97.2 nm.

Therefore, the wavelength of the photon emitted by the hydrogen atom is approximately 97.2 nm.

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Answer:

A force of 355 N is applied to an object that accelerates at a rate of 7.8 m/sec2 . What is the mass of the object ?

Explanation:

Answer:

he word that musicians use for frequency is pitch. The shorter the wavelength, the higher the frequency, and the higher the pitch, of the sound. In other words, short waves sound high; long waves sound low. ... In other words, it sounds higher

Explanation:

To make the red light appear green, you would need to be traveling at a speed of approximately 2.727×10⁸ m/s.

The color of light is determined by its wavelength. Red light has a longer wavelength than green light, with the given values of 650 nm and 550 nm, respectively.

The frequency of light is inversely proportional to its wavelength, so we can use the formula:

frequency = speed of light / wavelength

Given that the speed of light is 3×10⁸ m/s, we can calculate the frequencies of red and green light:

Frequency of red light = (3×10⁸ m/s) / (650×10⁻⁹ m) = 4.615×10¹⁴ s⁻¹

Frequency of green light = (3×10⁸ m/s) / (550×10⁻⁹ m) = 5.455×10¹⁴ s⁻¹

To perceive the red light as green, we need to match the frequencies. Since the speed of light remains constant, we can equate the two frequencies:

(3×10⁸ m/s) / (λ_red) = (3×10⁸ m/s) / (λ_green)

Simplifying the equation, we find:

λ_red = λ_green

From this, we can determine the speed required to make the red light appear green:

v = (λ_red - λ_green) / λ_green = (650×10⁻⁹ m - 550×10⁻⁹ m) / 550×10⁻⁹ m = 100×10⁻⁹ m / 550×10⁻⁹ m

v ≈ 2.727×10⁸ m/s

Therefore, in order for the red light to appear green, you would need to be moving at a velocity of approximately 2.727×10⁸ m/s.

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The electric and magnetic field amplitudes of an electromagnetic wave can be calculated using the power output of the source and the distance from the source. We can use the formula:

P = (1/2)ε₀cE₀²A,

where P is the power output, ε₀ is the permittivity of free space (8.854x10⁻¹² C²/(N·m²)), c is the speed of light (3x10⁸ m/s), E₀ is the electric field amplitude, and A is the surface area of a sphere with radius R.

First, let's calculate the surface area of the sphere at a distance of 15.0 m:

A = 4πR² = 4π(15.0 m)² ≈ 2827.43 m².

Now, rearranging the formula, we can solve for E₀:

E₀² = (2P) / (ε₀cA) = (2 * 960 W) / (8.854x10⁻¹² C²/(N·m²) * 3x10⁸ m/s * 2827.43 m²).

Calculating this expression gives us E₀² ≈ 8.76x10⁻⁶ N²/C².

Taking the square root, we find:

E₀ ≈ 9.36x10⁻⁴ N/C.

Finally, we can use the relationship between the electric and magnetic field amplitudes in an electromagnetic wave:

B₀ = E₀ / c,

where B₀ is the magnetic field amplitude.

Substituting the values, we get:

B₀ ≈ (9.36x10⁻⁴ N/C) / (3x10⁸ m/s) ≈ 3.12x10⁻¹² T.

Therefore, the electric field amplitude at a distance of 15.0 m from the source is approximately 9.36x10⁻⁴ N/C, and the magnetic field amplitude is approximately 3.12x10⁻¹² T.

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The minimum possible coefficient of static friction between bike tires and the ground is zero. This means that there is no requirement for static friction to exist in order for the bike to remain stationary or in motion.

Static friction is the force that prevents two surfaces from sliding against each other when there is no relative motion between them. It depends on the nature of the surfaces in contact and the force pressing them together. In the case of bike tires and the ground, the coefficient of static friction measures the ratio of the maximum static frictional force to the normal force between the tire and the ground.

If the coefficient of static friction were zero, it would imply that there is no need for static friction to keep the bike tires from slipping. This situation can occur when the surfaces are extremely smooth or when other forces, such as rolling resistance or air resistance, provide enough stability to maintain traction.

However, it's important to note that a zero coefficient of static friction can also indicate a lack of friction altogether, which could make it impossible for the bike tires to maintain contact with the ground and result in sliding or loss of control.

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The distance between the two 100 kg persons needs to be approximately 8.17 x 10^-4 meters (or 0.817 mm) in order for the force they exert on each other to be equal to 1 N.

To calculate the distance between two 100 kg persons so that the force they exert on each other is equal to 1 N, we can use Newton's law of universal gravitation.

The formula for gravitational force (F) between two objects is:

F = (G * m1 * m2) / r^2

where G is the gravitational constant (approximately 6.672 x 10^-11 N·m^2/kg^2), m1 and m2 are the masses of the objects, and r is the distance between the centers of the objects.

In this case, we want the force to be 1 N, and both persons have a mass of 100 kg. Substituting these values into the formula, we get:

1 N = (6.672 x 10^-11 N·m^2/kg^2 * 100 kg * 100 kg) / r^2

Simplifying the equation:

1 N = (6.672 x 10^-7 N·m^2) / r^2

Rearranging the equation to solve for the distance (r):

r^2 = (6.672 x 10^-7 N·m^2) / 1 N

r^2 = 6.672 x 10^-7 m^2

Taking the square root of both sides:

r ≈ 8.17 x 10^-4 m

Therefore, the distance between the two 100 kg persons needs to be approximately 8.17 x 10^-4 meters (or 0.817 mm) in order for the force they exert on each other to be equal to 1 N. Option B, 6.672 x 10^-7 m, appears to be a typographical error as it corresponds to the value of the gravitational constant rather than the distance.

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a) The work function of the metal is 2.00 eV.

b) When the photon energy is adjusted to 6.10 eV, the maximum kinetic energy of the photoelectrons will be 4.10 eV.

a) The work function (Φ) of the metal can be determined by subtracting the maximum kinetic energy (KEmax) of the photoelectrons from the energy of the incident photons (Ephoton).

Given:

The energy of incident photons (Ephoton) = 4.00 eV

The maximum kinetic energy of photoelectrons (KEmax) = 2.00 eV

To find the work function (Φ):

Φ = Ephoton - KEmax

Φ = 4.00 eV - 2.00 eV

Φ = 2.00 eV

Therefore, the work function of the metal is 2.00 eV.

b) To calculate the maximum kinetic energy of photoelectrons when the photon energy is adjusted to 6.10 eV, we use the same formula as in part (a).

Given:

The energy of incident photons (Ephoton) = 6.10 eV

To find the maximum kinetic energy of photoelectrons (KEmax):

KEmax = Ephoton - Φ

Using the previously determined work function (Φ) of 2.00 eV:

KEmax = 6.10 eV - 2.00 eV

KEmax = 4.10 eV

Therefore, when the photon energy is adjusted to 6.10 eV, the maximum kinetic energy of the photoelectrons will be 4.10 eV.

a) The work function of the metal is 2.00 eV.

b) When the photon energy is adjusted to 6.10 eV, the maximum kinetic energy of the photoelectrons will be 4.10 eV.

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Answer:

Because the hot tea is hot from a microwave or coffee machine when iced tea is cold from ice in the tea.

Explanation:

Answer:

It's often called the law of inertia. Acceleration is produced when a force acts on a mass. The greater the mass (of the object being accelerated) the greater the amount of force needed (to accelerate the object). ... A more massive object has a greater tendency to resist changes in its state of motion.

Explanation:

Answer: It's often called the law of inertia. Acceleration is produced when a force acts on a mass. The greater the mass (of the object being accelerated) the greater the amount of force needed (to accelerate the object). ... A more massive object has a greater tendency to resist changes in its state of motion.

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The error propagation equation for δk (the kinetic energy) is:

δk = √((1/4v^4) * δm² + m²v² * δv²).

To derive the error propagation equation for δk (the kinetic energy), we first need to understand what error propagation is.

Error propagation is a method used to estimate the uncertainty of a quantity that is derived from several other measured quantities that have uncertainties. In other words, it is a way to determine how the errors of the input quantities affect the error of the output quantity.

Now let's derive the error propagation equation for δk (the kinetic energy):

The kinetic energy (k) of an object can be calculated using the following equation:

k = 1/2mv^2

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

We can use the standard error propagation formula to find the uncertainty in k.

This formula is given as:

δk = √((∂k/∂m)² * δm² + (∂k/∂v)² * δv²)

where δm and δv are the uncertainties in the measured values of m and v, respectively.

To find ∂k/∂m and ∂k/∂v, we need to take the partial derivatives of k with respect to m and v.

∂k/∂m = 1/2v²

∂k/∂v = mv

Now we can substitute these values in the error propagation equation:

δk = √((1/2v²)² * δm² + (mv)² * δv²)

Therefore, the error propagation equation for δk (the kinetic energy) is:

δk = √((1/4v^4) * δm² + m²v² * δv²)

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The electron drift speed in the iron wire is approximately 4.49 mm/s. When electrons are subjected to an electric field they do move randomly, but they slowly drift in one direction, in the direction of the electric field applied. The net velocity at which these electrons drift is known as drift velocity.

The formula to calculate the electron drift speed is:

v_d = I / (n * A * q)

Where:

- v_d is the electron drift speed

- I is the electric current

- n is the number density of charge carriers (electrons)

- A is the cross-sectional area of the wire

- q is the charge of an electron

Given:

- I = 2.00 × 10^20 electrons

- Diameter of the wire = 3.20 mm

- Time = 4.50 s

First, we need to calculate the current (I) in Amperes:

I = (2.00 × 10^20 electrons) / (4.50 s)

I ≈ 4.44 × 10^19 A

Next, we need to determine the cross-sectional area (A) of the wire. The wire is cylindrical in shape, so we can use the formula for the area of a circle:

A = π * (diameter/2)^2

A = π * (3.20 mm/2)^2

A ≈ 8.03 mm^2

Converting the cross-sectional area to square meters:

A = 8.03 mm^2 * (1 m^2 / 1000 mm^2)

A ≈ 8.03 × 10^-6 m^2

The number density of charge carriers (n) is given by the ratio of the number of electrons (I) to the volume of the wire. Since we don't have the volume, we cannot calculate the exact number density. However, for a wire, the number density is typically on the order of 10^28 to 10^29 electrons per cubic meter.

Lastly, we know that the charge of an electron (q) is approximately 1.6 × 10^-19 C.

Using the formula for electron drift speed, we can calculate:

v_d = (4.44 × 10^19 A) / (10^28 electrons/m^3 * 8.03 × 10^-6 m^2 * 1.6 × 10^-19 C)

v_d ≈ 4.49 mm/s

Therefore, the electron drift speed in the iron wire is approximately 4.49 mm/s.

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At a frequency of 500 Hz, the impedance of the circuit is approximately 180.026Ω, and the phase angle of the source voltage with respect to the current is approximately 0.637°.

A) To compute the impedance of the circuit, we use the formula:

Z = √(R² + (XL - XC)²)

Where Z is the impedance, R is the resistance, XL is the inductive reactance, and XC is the capacitive reactance.

Given:

Resistance (R) = 180Ω

Inductance (L) = 0.150H

Capacitance (C) = 0.600μF

= 0.600 × 10⁻⁶ F

At frequency f1 = 500 Hz:

XL = 2πf1L

XC = 1/(2πf1C)

Calculating XL and XC:

XL = 2π(500 Hz)(0.150 H)

= 471 Ω

XC = 1/(2π(500 Hz)(0.600 × 10⁻⁶ F))

≈ 5307 Ω

Using the formula for impedance:

Z1 = √(R² + (XL - XC)²)

= √(180² + (471 - 5307)²)

≈ 180.026 Ω

At frequency f2 = 1000 Hz:

XL = 2πf2L

XC = 1/(2πf2C)

Calculating XL and XC:

XL = 2π(1000 Hz)(0.150 H)

= 942 Ω

XC = 1/(2π(1000 Hz)(0.600 × 10⁻⁶ F))

≈ 2653 Ω

Using the formula for impedance:

Z2 = √(R² + (XL - XC)²)

= √(180² + (942 - 2653)²)

≈ 180.134 Ω

B) The phase angle (θ) of the source voltage with respect to the current can be calculated using the formula:

θ = atan((XL - XC)/R)

At frequency f1:

θ1 = atan((XL - XC)/R)

= atan((471 - 5307)/180)

≈ 0.637°

At frequency f2:

θ2 = atan((XL - XC)/R)

= atan((942 - 2653)/180)

≈ 0.318°

At a frequency of 500 Hz, the impedance of the circuit is approximately 180.026Ω, and the phase angle of the source voltage with respect to the current is approximately 0.637°. At a frequency of 1000 Hz, the impedance of the circuit is approximately 180.134Ω, and the phase angle is approximately 0.318°.

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The gauge pressure that someone would measure for the can of soda located at sea level is 2.0 atm.

Gauge pressure is the pressure measured relative to atmospheric pressure. At sea level, the atmospheric pressure is approximately 1.0 atm. To find the gauge pressure, we subtract the atmospheric pressure from the internal absolute pressure.

Gauge pressure = Internal absolute pressure - Atmospheric pressure

Given that the internal absolute pressure is 3.0 atm and the atmospheric pressure is 1.0 atm, we can substitute these values into the equation:

Gauge pressure = 3.0 atm - 1.0 atm = 2.0 atm

If the can of soda is located at sea level, someone would measure a gauge pressure of 2.0 atm. Gauge pressure represents the pressure above or below atmospheric pressure, and in this case, the can has an internal pressure that is 2.0 atm higher than the atmospheric pressure at sea level.

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If a buffer solution is 0.210 m in a weak acid and 0.470 m in its conjugate base. The pH of the buffer solution is approximately 4.53.

To determine the pH of a buffer solution, we can use the Henderson-Hasselbalch equation, which is given by

pH = pKa + log ([A-] / [HA])

Where:

pH is the logarithmic measure of the hydrogen ion concentration in the solution.

pKa is the negative logarithm of the acid dissociation constant (Ka) of the weak acid.

[A-] is the concentration of the conjugate base.

[HA] is the concentration of the weak acid.

In this case, the concentration of the weak acid ([HA]) is 0.210 M, and the concentration of the conjugate base ([A-]) is 0.470 M. The acid dissociation constant (Ka) is given as 6.7 × [tex]10^{-5}[/tex].

First, let's calculate the pKa

pKa = -log(Ka) = -log(6.7 × [tex]10^{-5}[/tex]) = 4.18

Next, substitute the given values into the Henderson-Hasselbalch equation:

pH = 4.18 + log(0.470 / 0.210) = 4.18 + log(2.238) = 4.18 + 0.35

pH = 4.53

Therefore, the pH of the buffer solution is 4.53.

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Answer: D all of the above

Explanation: Coal, Graphite, Diamond are all allotropes of Carbon. Hope this helps :)

Answer:

liquids and gases

Explanation:

Liquids and gases are considered to be fluids because they yield to shearing forces, whereas solids resist them.

Answer:

Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

Explanation:

The magnetic flux if the magnetic field vector is b=(-20 t)i (10 t)k and the area vector is a=(-50 m2)j (8 m2) k is 1000 t j + 80 t k.

The magnetic flux is calculated as follows:

[tex]\phi = \vec{B} \cdot \vec{A}[/tex]

where  

B is the magnetic field vector,  

A is the area vector, and ϕ is the magnetic flux.

In this case, we have:

[tex]\vec{B} = (-20 t)i + (10 t)k[/tex]

and

[tex]\vec{A} = (-50 m^2)j + (8 m^2) k[/tex]

Substituting these values into the equation for magnetic flux, we get:

[tex]\begin{aligned}\phi &= (-20 t)i + (10 t)k \cdot (-50 m^2)j + (8 m^2) k \\&= -20 t \cdot (-50 m^2)j + 10 t \cdot 8 m^2 k \\&= 1000 t j + 80 t k\end{aligned}[/tex]

Therefore, the magnetic flux is a vector with a magnitude of 1000t and a direction of j+k. Note that the magnetic flux is a scalar quantity, so the vector notation is only used to indicate the direction of the flux.

The magnetic flux can also be calculated as follows:

[tex]\phi = \int_A \vec{B} \cdot d\vec{S}[/tex]

where A is the area of the surface, and d

S is a small element of surface area. In this case, the area of the surface is a rectangle with dimensions 50×8 meters. The magnetic field is uniform, so we can calculate the magnetic flux as follows:

[tex]\begin{aligned}\phi &= \int_A \vec{B} \cdot d\vec{S} \\&= \int_{-50}^{50} \int_{-8}^8 (-20 t)i + (10 t)k \cdot dx dy \\&= \int_{-50}^{50} (-20 t) \cdot dy + \int_{-8}^8 (10 t) \cdot dx \\&= 1000 t j + 80 t k\end{aligned}[/tex]

The answer is: 1000 t j + 80 t k

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The statement is true. When one projects an object vertically upward from the ground, that object will reach a maximum height h before it is brought back down to earth by the force of gravity.

The laws of motion, more especially the principles of projectile motion, are the ones that rule over this behaviour. When the object is propelled forward, its initial velocity works against the gravitational pull, causing it to slow down until it reaches its highest point. This continues until the object has reached its highest position. After reaching this point, the object's velocity stops being positive and it begins a free fall towards the ground as a result of the force of gravity.

The initial velocity of the object, the angle at which it is launched, and the force of gravity all play a role in determining the maximum height h that it is possible to reach. Kinematic equations can be used to determine the answer to this question. It is essential to keep in mind, however, that the maximum height will also be determined by any external forces that are operating on the object, such as the resistance posed by the air.

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Answer:C

Explanation:I think sorry if it’s wrong

Answer: for insulation of heat

Explanation:

Windows in cold countries have double glazing windows to provide a barrier against the outside temperature by creating a buffer zone between two glasses.

The air or any other gas-filled between the glasses act as an insulator and offer great resistance to outside temperature thereby maintaining the inside temperature intact.

Answer:

It happens because the Earth is tilted on its axis around 23 degrees therefore the sun normally never sets at north Pole in summers. The sun doesn't set at Arctic Circle on North pole from about April 19 to August 23 each year due to this phenomenon.

The temperature of the hotter star ([tex]T_h[/tex]) is equal to the square root of the surface temperature of the cooler star (T), and the ratio of the peak-intensity wavelengths is proportional to the inverse cube of the temperature ratio.

Part A: Let's denote the temperature of the hotter star as [tex]T_h[/tex]. According to the Stefan-Boltzmann law, the total energy radiated by a blackbody is proportional to the fourth power of its temperature. Since both stars radiate the same total energy per second, we can write:

[tex]T_h^4 = T^4[/tex]

Taking the fourth root of both sides, we get:

[tex]T_h = T^{(\frac {1}{4})}[/tex]

Part B: The peak intensity wavelength (λmax) of a blackbody radiation is inversely proportional to its temperature.

According to Wien's displacement law, we can express the ratio of peak-intensity wavelengths ([tex]\lambda_{max, hot}/ \lambda_{max, cool}[/tex]) as the ratio of their temperatures:

[tex]\frac{\lambda_{max, hot}}{ \lambda_{max, cool}} = \frac{T_h}{T}[/tex]

Substituting the relationship we derived in Part A, we have:

[tex]\frac{\lambda_{max, hot}}{ \lambda_{max, cool}} = \frac{T^{\frac{1}{4}} }{T}[/tex]

Simplifying, we get:

[tex]\frac{\lambda_{max, hot}}{ \lambda_{max, cool}} = T^{\frac{-3}{4}} }[/tex]

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Answer:

The kinetic energy of the baseball is 306.25 joules.

Explanation:

SInce the baseball can be considered a particle, that is, that effects from geometry can be neglected, the kinetic energy ([tex]K[/tex]), in joules, is entirely translational, whose formula is:

[tex]K = \frac{1}{2}\cdot m\cdot v^{2}[/tex] (1)

Where:

[tex]m[/tex] - Mass, in kilograms.

[tex]v[/tex] - Speed, in meters per second.

If we know that [tex]m = 0.5\,kg[/tex] and [tex]v = 35\,\frac{m}{s}[/tex], then the kinetic energy of the baseball thrown by the player is:

[tex]K = \frac{1}{2}\cdot m \cdot v^{2}[/tex]

[tex]K = 306.25\,J[/tex]

The kinetic energy of the baseball is 306.25 joules.

The image of the shopper is 75.0 cm from the mirror's surface, and it is virtual.

The magnification (m) of an image formed by a convex mirror is given by the formula:

m = -d_i / d_o,

where d_i is the distance of the image from the mirror's surface and d_o is the distance of the object from the mirror's surface. In this case, the magnification is given as 0.250.

Given that the shopper is standing 3.00 m from the convex mirror (d_o = 3.00 m) and the magnification is 0.250, we can rearrange the formula to solve for d_i:

d_i = -m * d_o.

Substituting the values into the formula:

d_i = -0.250 * 3.00,

   = -0.75 m.

The negative sign indicates that the image is virtual, meaning it cannot be projected onto a screen. Taking the absolute value, the image is 0.75 m from the mirror's surface.

Converting 0.75 m to centimeters, we get 75.0 cm.

The image of the shopper is located 75.0 cm from the convex mirror's surface, and it is a virtual image. This calculation utilizes the magnification formula for a convex mirror to determine the distance of the image based on the given magnification and object distance.

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Answer:

d=v1t - .5at^2

d=4.88 x .872 - 0.5 x (4.88/0.872) x 0.872^2

d=4.255 - 2.12

d= 2.135m

Explanation:

acceleration is negative because she is slowing down.

Answer:

Hereeeeeeeeeeeeeeeeeee