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Lila is a track and field athlete. She has to complete four laps around the track, which is 400 meters. The race took her 6 minutes to complete. What is her average speed to the first decimal point in m/s?

Answer:

The kinetic coefficient of friction between box and floor is 0.443.

Explanation:

Let suppose that the box is accelerated uniformly, the acceleration ([tex]a[/tex]), measured in meters per square second, is determined by the following kinematic formula:

[tex]a = \frac{v_{f}-v_{o}}{t}[/tex] (1)

Where:

[tex]v_{o}[/tex], [tex]v_{f}[/tex] - Initial and final speeds of the box, measured in meters per second.

[tex]t[/tex] - Time, measured in seconds.

If we know that [tex]v_{o} = 0\,\frac{m}{s}[/tex], [tex]v_{f} = 2\,\frac{m}{s}[/tex] and [tex]t = 4\,s[/tex], then the acceleration experimented by the box is:

[tex]a = \frac{2\,\frac{m}{s}-0\,\frac{m}{s} }{4\,s}[/tex]

[tex]a = 0.5\,\frac{m}{s^{2}}[/tex]

Based on the body diagram, we proceed to form the equations of equilibrium:

[tex]\Sigma F_{x} = P\cdot \cos \theta -\mu_{k}\cdot N = m\cdot a[/tex] (1)

[tex]\Sigma F_{y} = N - m\cdot g - P\cdot \sin \theta = 0[/tex] (2)

Where:

[tex]P[/tex] - Magnitude of the force exerted on the box, measured in newtons.

[tex]\theta[/tex] - Direction of the force exerted on the box, measured in sexagesimal degrees.

[tex]\mu_{k}[/tex] - Kinetic coefficient of friction between box and floor, dimensionless.

[tex]N[/tex] - Normal force from the floor to the box, measured in newtons.

[tex]m[/tex] - Mass of the block, measured in kilograms.

[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.

Now we proceed to solve the system of equation for the kinetic coefficient of friction between box and floor:

By (1)

[tex]\mu_{k}\cdot N = P\cdot \cos \theta -m\cdot a[/tex]

[tex]\mu_{k} = \frac{P\cdot \cos \theta - m\cdot a}{N}[/tex]

By (2)

[tex]N = m\cdot g +P\cdot \sin \theta[/tex]

And then, we get the resulting expression:

[tex]\mu_{k} = \frac{P\cdot \cos \theta - m\cdot a}{m\cdot g + P\cdot \sin \theta}[/tex] (3)

If we know that [tex]P = 400\,N[/tex], [tex]\theta = 50^{\circ}[/tex], [tex]m = 25\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]a = 0.5\,\frac{m}{s^{2}}[/tex], then the kinetic coefficient of friction between box and floor is:

[tex]\mu_{k} = \frac{(400\,N)\cdot \cos 50^{\circ}-(25\,kg)\cdot \left(0.5\,\frac{m}{s^{2}} \right)}{(25\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)+(400\,N)\cdot \sin 50^{\circ}}[/tex]

[tex]\mu_{k} = 0.443[/tex]

The kinetic coefficient of friction between box and floor is 0.443.

The kinetic coefficient of friction between box and floor is 0.443.It is the ratio of friction force and the normal recation force.

It is a type of opposition force acting on the surface of the body that tries to oppose the motion of the body. its unit is Newton (N).

Mathematically it is defined as the product of the coefficient of friction and normal reaction.

The given data in the problem is;

F is the force =400 N

m is the mass of box= 25-kg

u is the velocity starting from rest=0

v is the velocity achieved = 2.0 m/s

t is the time = 4.0 s.

[tex]\rm \mu[/tex] is  the coefficient of kinetic friction between box and floor.

The aceleration is found as;

[tex]\rm a= \frac{v_f-v_u}{t} \\\\ \rm a= \frac{2-0}{4} \\\\ \rm a= 0.5 m/sec^2[/tex]

The normal reaction force is find as;

[tex]N= mg +P sin \theta[/tex]

The cofficient of the kinetic coefficient of friction between box and floor;

[tex]\rm \mu_k = \frac{Pcos \theta - ma }{N } \\\\ \rm \mu_k = \frac{Pcos \theta - ma }{ mg +P sin \theta } \\\\ \rm \mu_k = \frac{400 cos 50^0 - 25 \times 0.5 }{ 25 \times 9.81 +400 \times sin 50^0 } \\\\ \rm \mu_k =0.443[/tex]

Hence he kinetic coefficient of friction between box and floor is 0.443.

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Answer:

a. Any one way then I can say that Aluminum sulfide has mass per mole of ≈150.2g while aluminum has mass per mole of 26.9g

b. Sulfur is an element but aluminum sulfide is a compound

c.Beryllium and chlorine

d. BeCl2

e.i. Metals form ions by losing electrons but nonmetals form ions by gaining electrons

ii.A metal can react with an acid to produce a salt a nonmetal doesnt

iii. A metal forms ionic compounds whilst nonmetals form covalent compounds

Answer  he would go to court veto bill

Explanation

that how it works

Answer:

constant velocity means that both the speed and direction do not change . An object moving in a circular path with constant speed does not have a constant velocity because the direction of the velocity is constantly changing. This implies that an object moving at a constant speed in a circular path is accelerating

Answer:

The mass of the object is 40 Kg

Explanation:

Net Force

According to the second Newton's law, the net force exerted by an external agent on an object is:

F = m.a

Where:

a = acceleration of the object.

m = mass of the object.

The mass can be calculated by solving for m:

[tex]\displaystyle m=\frac{F}{a}[/tex]

The object has a net force of F=600 N acting on it and travels at [tex]a=15\ m/s^2[/tex], thus the mas is:

[tex]\displaystyle m=\frac{600}{15}[/tex]

m = 40 Kg

The mass of the object is 40 Kg

Answer:

f

Explanation:

Answer:

The pressure is  [tex]P = 1.31*10^{5} \ Pa[/tex]

Explanation:

From the question we are told that

    The depth of the swimming pool is  [tex]d = 3.00 \ m[/tex]

     The density of water is  [tex]\rho = 1.00*10^{3} \ kg /m^3[/tex]

Generally the  total pressure exerted on the bottom of the swimming pool is mathematically represented as

          [tex]P = P_o + \rho * g * h[/tex]

Here [tex]P_o[/tex] is the atmospheric pressure with value

        [tex]P_o = 101325 \ Pa[/tex]

So

        [tex]P = 101325 + [1000 * 9.8 * 3][/tex]

=>     [tex]P = 130725 \ Pa[/tex]

=>    [tex]P = 1.31*10^{5} \ Pa[/tex]

Answer:

I think carbon dioxide is a mixuture and Methane is a compound

Explanation:

The correct options that describe the physical properties of matter are "A substance's resistance to flow," and "A substance's ability to conduct electricity." The correct options are B and C.

Physical properties of matter are characteristics that can be observed or measured without changing the substance's identity. These properties can help us identify and classify different substances.

Here in the Question,

Let's consider each option one by one:

A. A substance's pH is a chemical property of matter, which indicates whether a substance is acidic, neutral, or basic. It depends on the substance's chemical composition and the concentration of hydrogen ions in it. Therefore, this option is not a physical property.

B. A substance's resistance to flow is a physical property, also known as viscosity. It refers to how easily a substance can flow or be poured. For example, honey has a high viscosity, while water has a low viscosity. This property depends on the intermolecular forces between the molecules of the substance, which affect how closely they pack together. Therefore, this option is a physical property.

C. A substance's ability to conduct electricity is a physical property that depends on its structure and the presence of charged particles, such as ions or electrons. Substances that can conduct electricity are called conductors, while those that cannot are called insulators. Metals are good conductors of electricity, while plastics are good insulators. Therefore, this option is also a physical property.

D. Whether a substance rusts is a chemical property that indicates how a substance reacts with other substances, specifically with oxygen. Rusting occurs when iron or steel reacts with oxygen in the presence of water, forming a reddish-brown compound called iron oxide. Therefore, this option is not a physical property.

E. A substance's inability to combine with other substances is also a chemical property that depends on the substance's reactivity. Inability to combine with other substances may be due to a substance's stable electronic configuration, such as noble gases. Therefore, this option is also not a physical property.

Therefore, options B and C are true.

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Answer:

THE GROUND IS THE MEDIUM OF SEISMIC WAVES

Answer:

thermal energy

Explanation:

Weight = mass × acceleration due to gravity, so

52 N = m (9.8 m/s²)

m = (52 N) / (9.8 m/s²) ≈ 5.3 kg

Answer:

is the formula is F=MA so

F=100kg×4m/s=400n

so the answer is 400n

Explanation:

[tex]advantage[/tex]

It is Sensitivity to surface defects. ...

[tex]disadvantage[/tex]

There is a major heat loss during cycling eddy currents due to friction in the magnetic circuit, especially where the core is saturated

Please mark as brainliest answer

Answer:

a. Point A

b. 20 V

c. 100 J

Explanation:

a. Point A is at a higher potential because there is a positive sign in front of its magnitude. Since it is a positive integral value, and has a higher magnitude than point B which is at -4, point A is thus at a higher potential than point B.

b. The potential difference between the two points ΔV = A - B

= +16 V - (-4 V)

= +16 V + 4 V

= + 20 V

c. The work done, W in moving a charge Q across a potential difference ΔV is W = QΔV

So, since Q = 5 C and ΔV = + 20 V  

W = QΔV

= 5 C × (+ 20 V)

= 100 J

Answer:

15 cm

Explanation:

Dari pertanyaan yang diberikan di atas, diperoleh data sebagai berikut:

Gaya 1 (F₁) = 225 N

Jarak terpisah 1 (d) = 5 cm

Gaya 2 (F₂) = 25 N

Jarak terpisah 2 (d₂) =?

Kita dapat memperoleh persamaan yang berkaitan dengan gaya dan jarak muatan dua titik dengan menggunakan rumus berikut:

F = Kq₁q₂ / d²

Perbanyak silang

Fd² = Kq₁q₂

Menjaga Kq₁q₂ konstan, kita memiliki:

F₁d₁² = F₂d₂²

Dengan rumus di atas maka diperoleh jarak sebagai berikut:

Gaya 1 (F₁) = 225 N

Jarak terpisah 1 (d) = 5 cm

Gaya 2 (F₂) = 25 N

Jarak terpisah 2 (d₂) =?

F₁d₁² = F₂d₂²

225 × 5² = 25 × d₂²

225 × 25 = 25 × d₂²

5625 = 25 × d₂²

Bagilah kedua sisinya dengan 25

d₂² = 5625/25

d₂² = 225

Hitung akar kuadrat dari kedua sisi

d₂ = √225

d₂ = 15 cm

Oleh karena itu, muatan dua titik harus berjarak 15 cm untuk memiliki gaya tarik 25 N

Answer:

Concept: Physical Constants

The difference between Length and Time is: Length is a measure of distance while Time is a quantity or measure of period.

Length can defined as a fundamental quantity that describe the total space occupied by an object from end to end or the distance of an object from end to end.

Time can be defined the duration of an occurrence in space. Time is so important as it helps us adequately know the period of an event or occurrence.

In conclusion, The difference between Length and Time is: Length is a measure of distance while Time is a quantity or measure of period.

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Answer:

0.373 seconds. First, calculate the initial vertical velocity of the shell. 800sin(30) = 800*0.5 = 400 m/s Now the formula for the distance traveled is d = 400 m/s * T + 0.5A T^2 Substituting known values gives.

Explanation:

Answer:

[tex]\theta=\tan^{-1}\dfrac{a}{g}[/tex]

Explanation:

Here we are assuming that the car is moving in a straight line and is traveling on a smooth surface. When the car is moving with acceleration [tex]a[/tex] the bob moves in the opposite direction with the same acceleration. Gravity is acting on the bob so it is experiencing an acceleration of [tex]g[/tex] downwards.

The angle between the acceleration [tex]a[/tex] and the acceleration due to gravity [tex]g[/tex] is

[tex]\theta=\tan^{-1}\dfrac{a}{g}[/tex].

Answer:

5000 m³

Explanation:

density = mass / volume

mass = density × volume

mass = 1000 × 5

mass = 5000 ( kg )

Answer:

7.35m/s²

Explanation:

From the question we are not told what to find but we can as well find the acceleration of the wagon.

According to newton second law of motion

[tex]\sum F_x = ma_x\\Fm - Ff = ma_x\\Fm - \mu R = ma_x\\Fm- \mu mg = ma_x\\[/tex]

Fm is the moving force = 410N

[tex]\mu[/tex] is the coefficient of friction = 0.18

m is the mass = 45kg

g is the acceleration dur to gravity = 9.8m/s²

a is the acceleration of the wagon

Substitute the given data into the equation ang get ax

[tex]Fm- \mu mg = ma_x\\410 - (0.18)(9.8)(45) = 45a_x\\410 - 79.38 = 45a_x\\330.62 = 45a_x\\a_x = 330.62/45\\a_x = 7.35m/s^2\\[/tex]

Hence the acceleration of the wagon is 7.35m/s²

Answer:

What is quantum physics? Put simply, it's the physics that explains how everything works: the best description we have of the nature of the particles that make up matter and the forces with which they interact. Quantum physics underlies how atoms work, and so why chemistry and biology work as they do.

Answer: The plasma membrane is called a selectively permeable membrane as it permits the movement of only certain molecules in and out of the cells. Not all molecules are free to diffuse. If plasma membrane ruptures or breaks down then molecules of some substances will freely move in and out of the cells. Semipermeable membrane describes a membrane that allows some particles to pass through (by size), whereas the selectively permeable membrane "chooses" what passes through (size is not a factor). Selective permeability is a property of cellular membranes that only allows certain molecules to enter or exit the cell. This is important for the cell to maintain its internal order irrespective of the changes to the environment. For example, water, ions, glucose and carbon dioxide may need to be imported or exported from the cell depending on its metabolic activity. Similarly, signaling molecules may need to enter the cell and proteins may need to be released into the extracellular matrix. The presence of a selectively permeable membrane allows the cell to exercise control over the quantum, timing and rate of movement of these molecules.

Explanation: hope this helps you with your work/assingment! Have a wonderful day/night!

Answer:

I'm thinking Newton's first law of motion.

Explanation:

"An object at rest remains at rest, or if in motion, remains in motion at a constant velocity unless acted on by a net external force."

Answer:

ineria

Explanation:

It is due to her inertia of motion that kept her moving forward.

We have Nina who is riding skateboard.

We have to determine why Nina fell off the skateboard on rough pavement.

A property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force.

According to the question -

Before the rough patch, Nina was riding smoothly. However as soon as she enters the rough patch, the rough patch acts as an obstruction to the forward movement of skateboard. The skateboard and Nina are both moving with same velocity. The skateboard is in contact with the rough patch and as soon as the skateboard's motion is obstructed, the skateboard comes to rest but due to the inertia of motion, Nina continues to move with the same forward velocity. In this way, Nina falls ahead of skateboard.

Hence, it is due to her inertia of motion that kept her moving forward.

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