A student slides her 80. 0-kg desk across the level floor of her dormitory room a distance 2. 00 m at constant speed. If the coefficient of kinetic friction between the desk and the floor is 0. 400, how much work did she do?.

By Newton's second and third laws, we have the following net forces at

\(\sum F_x = -T_1 \cos(60^\circ) + T_2 \cos(60^\circ) = 0\)

\(\sum F_y = T_1 \sin(60^\circ) + T_2 \sin(60^\circ) - 600 \,\mathrm N = 0\)

Together, these equations tell us \(\boxed{T_1=T_2\approx 346 \,\mathrm N}\).

\(\sum F_x = T_3 \cos(20^\circ) - T_2 \cos(60^\circ) - T_5 = 0\)

\(\sum F_y = T_3 \sin(20^\circ) - T_2 \sin(60^\circ) = 0\)

\(\sum F_x = -T_4 \cos(20^\circ) + T_1 \cos(60^\circ) + T_5 = 0\)

\(\sum F_y = T_4 \cos(20^\circ) - T_1 \sin(60^\circ) = 0\)

Combining the horizontal force equations for points B and C and using the fact that \(T_1=T_2\) gives

\((T_3 \cos(20^\circ) - T_2 \cos(60^\circ) - T_5) + (-T_4  \cos(20^\circ) + T_1 \cos(60^\circ) + T_5) = 0 + 0\)

\(\implies (T_3 - T_4) \cos(20^\circ) = 0 \implies T_3=T_4\)

Then combining the vertical force equations for B and C, we find

\((T_3 \sin(20^\circ) - T_2 \sin(60^\circ)) + (T_4 \sin(20^\circ) - T_1 \sin(60^\circ)) = 0 + 0\)

\(\implies 2 T_3 \sin(20^\circ) - 2 T_1 \sin(60^\circ) \implies T_3 = \dfrac{\sin(60^\circ)}{\sin(20^\circ)} T_1\)

so that \(\boxed{T_3 = T_4 \approx 877 \,\mathrm N}\)

Lastly solve for \(T_5\) using either horizontal force equation for B or C.

\(-T_4 \cos(20^\circ) + T_1 \cos(60^\circ) + T_5 = 0\)

\(\implies T_5 = \left(\dfrac{\sin(60^\circ)}{\sin(20^\circ)} - \cos(60^\circ)\right) T_1 \implies \boxed{T_5 \approx 651\,\mathrm N}\)

Answer:

My arms are doing a negative work

Explanation:

When you set something on the ground, the displacement of the object set towards the ground is in the downward direction. which means that, in this case, there is a downward displacement.

As the object is set on the ground, the force exerted by the arms on the object acts in the upward direction.

Summarily, direction of force is upwards while the direction of displacement is downwards.

Since the force and displacement act in opposite direction, a negative work is said to be done.

Answer:

F = 20 N

Explanation:

Given that,

Mass of the football, m = 2 kg

Initial speed, u = 0

Final speed,v = 5 m/s

The time of contact, t = 0.5 s

We need to found the average force applied by the footballer  on the football. We can find it using the formula.

\(F=\dfrac{m(v-u)}{t}\\\\F=\dfrac{2\times (5-0)}{0.5}\\\\F=20\ N\)

So, the required force is 20 N.

Answer:

F=20

Explanation:

f=20

Answer:

Central City is the county seat and the most populous municipality of Gilpin County. The city is a historic mining settlement founded in 1859 during the Pike's Peak Gold Rush and came to be known as the "Richest Square Mile on Earth".

Answer:

hi

Explanation:

hi

Answer:

option C

Explanation:

Final velocity of the object is 114 m / s. Hence, final velocity of the object is 114 m / s.

Answer:

Relationship between population size, carrying capacity, and limiting factors is described below.

Explanation:

1. There are four variables which govern changes in population size.

births

deaths

immigration

emigration

A population gains individuals by birth and immigration and loses individuals by death and emigration.

2. Populations vary in their capacity to grow. The maximum rate at which a population can increase when resources are unlimited and environmental conditions are ideal is termed the population's biotic potential.

3. There are always limits to population growth in nature. Populations cannot grow exponentially indefinitely. Exploding populations always reach a size limit imposed by the shortage of one or more factors such as water, space, and nutrients or by adverse conditions such as disease, drought and temperature extremes.

4. The factors which act jointly to limit a population's growth are termed the environmental resistance. The interplay of biotic potential and density-dependent environmental resistance keeps a population in balance.

5. Carrying Capacity

For a given region, carrying capacity is the maximum number of individuals of a given species that an area's resources can sustain indefinitely without significantly depleting or degrading those resources. Determining the carrying capacities for most organisms is fairly straightforward. For humans carrying capacity is much more complicated. The definition is expanded to include not degrading our cultural and social environments and not harming the physical environment in ways that would adversely affect future generations.

6. Population Impact

Homo sapiens is a species possessing a diversity of individual needs. Thus, sub-populations will have different requirements and different impacts on the environment. For example 100 million vegetarians will have a significantly different environmental impact than 100 million meat-eaters. This can be demonstrated by comparing the affect on water supplies by both sub-populations. About 1000 tons of water are needed to produce 1 ton of grain. Almost 40% of all grain is used in meat and poultry production. Add to this the amount of water that goes into the production of meat, and you can see that meat comsumption places more stress on global water supplies than grain consumption.

Hope this helps (: Mark me brainliest if its good to you.

Answer:

0.4

Explanation:

time is disance divided by speed.

Answer:

you havent given the full question

but im guessing momentum

momentum is the quantity of motion of a moving body, measured as a product of its mass and velocity or the impetus gained by a moving object.

Explanation:

as the child is pushed, it gathers momentum as its weight allows it be pushed forward, and the velocity is the speed driven by the amount of force the parent pushes on the child whilst they are swinging. The momentum is the result of this action

the equation that links these factors together are

p = mv

p = momentum

m = mass

v = velocity

hope i got it right ._.

Answer:

0.89 m/s^2

Explanation:

Here we are given that,

As we know that in case of uniform circular motion , centripetal acceleration is given by,

\(\implies a_c =\dfrac{v^2}{r} \\\)

And here ,

\(\implies v = 76km/h =\dfrac{5}{18}\times 76\ m/s \\\)

\(\implies v = 21.1 \ m/s \\\)

Also ,

\(\implies r =\dfrac{d}{2} \\\)

\(\implies r = 0.5km =\boxed{500m} \\\)

Now substitute the respective values,

\(\implies a_c = \dfrac{21.1\times 21.1 }{500} m/s^2 \\\)

\(\implies\underline{\underline{ a_c = 0.89\ m/s^2}} \\\)

and we are done!

Answer:

dame la marca más inteligente, por favor

Explanation:

En el campo de la medicina, es la respuesta del cuerpo a una presión física, mental o emocional. El estrés produce cambios químicos que elevan la presión arterial, la frecuencia cardíaca y las concentraciones de azúcar en la sangre. También suele producir sentimientos de frustración, ansiedad, enojo o depresión.

Answer:

El estrés es la reacción del cuerpo al sentirse amenazado o bajo presión.

Explanation:

The properties of the electric fields and particle acceleration are as follows;

1. 3.75 × 10¹² electrons

2. Attracted

3. -1348.5 N

4. 1348.5 N

5. 8890 N

6. 1.044 × 10⁻⁴ C

7. The direction is downwards

8. Please find attached the required drawing created with MS Word

9. 2.87 × 10⁸ m/s²

10. Please find attached the drawing of the path of the proton created with MS Word.

An electric field is a vector that describes the electric force experienced by a charged particle at any point in space.

1. The charge of an electron is approximately -1.6 × 10^(-19) C. If the glass rod has a charge of -0.6 μC, which is equivalent to -0.6 × 10^(-6) C, then the number of electrons added to the rod is (-0.6 × 10^(-6))/(-1.6 × 10^(-19) C/electron) = 3.75 × 10^12 electrons.

2. The charges of the pith ball and the metal plate are opposite, therefore, the pith ball and metal plate are attracted to each other.

3. To calculate the force on the negatively charged object from problem 2, Coulomb's law can be used as follows;

F = k·q₁·q₂/r²

Where;

k = Coulomb's constant  (8.99 × 10⁹ N·m²/C²)

q₁ and q₂ = The charges of the two objects

r = The distance between them

Therefore;

F = (8.99×10⁹ N·m²/C²) × (10 × 10⁻⁶ C) × (-6 × 10⁻⁶ C)/(0.02 m)² = -1348.5 N

4. The force on the positively charged object from problem 2 is equal in magnitude but opposite in direction to the force on the negatively charged object, so it is 1348.5 N

5. To calculate the electric field a distance of 4.0 mm away from a -2.0 μC charge, we can use the formula; E = k × q/r², where k is Coulomb's constant, and we get;

E = (8.99 × 10⁹ N·m²/C²)×(-2×10⁻⁶ C)/(4 × 10⁻³ m)² = -1123750000 N/C

The force on a -8.0 μC charge placed at this point can be calculated using the formula; F = q·E, where q is the charge and E is the electric field.

Plugging in the values, we get; F = (-8 × 10^(-6) C) × (-1123750000 N/C) = 8990 N

6. To float your sister in the air using opposing electric charges, you need to create an electrostatic force that is equal and opposite to her weight. Her weight is; m × g = 40 kg × 9.8 m/s² = 392 N

To calculate how much charge you need to deposit both on her and on a metal plate directly below her to create this force, we can use Coulomb's Law: F = k·q₁·q₂/r², where

k = Coulomb's constant

r = The distance between her and the plate = 0.5 m

The charge on the plate = The charge on her

Therefore;

q₁ = q₂ = q
Therefore;

q = √(F × r²/k) = √(392 × (0.5)²/(8.99 × 10⁹) ≈ 1.044 × 10⁻⁴

The charge required, q ≈ 1.044 × 10⁻⁴ C

7. The direction of the force on a proton when between two plates with a vertical electric field pointing downwards would be downwards as well since protons are positively charged particles.

8. Please find attached the drawing of the electric field lines

9. The electric force on the proton can be obtained from the formula;

F = q·E

Where;

q = The charge of the proton

E = The electric field

Therefore;

The electric force on the proton is (1.6 × 10⁻¹⁹) × (3.0 N/C) = 4.8 × 10⁻¹⁹ N

The formula for the acceleration of the proton is; a = F/m

Where;

a = The acceleration of the proton

m = The mass of the proton ≈ 1.67 × 10⁻²⁷ kg

Therefore;

a = (4.8 × 10⁻¹⁹ N)/(1.67 × 10⁻²⁷ kg) ≈ 2.87 × 10⁸ m/s²

The direction of the acceleration of the proton would be, downward, which is in the same direction as the electric field

10. Please find attached drawing of the path of the proton as it travels through the plate

Learn more on electric fields here: https://brainly.com/question/28128803

#SPJ1

Answer:

The spring constant will be "1333.33 N/m".

Explanation:

The given values are:

Mass,

m = 1.2 kg

Displacement compression,

x = 0.15 m

Block's velocity,

\(v_i=5 \ m/s\)

As we know,

⇒  \(E_i=E_f\)

or,

⇒  \(K_i+v_i=K_f+v_f\)

⇒  \(\frac{1}{2}mv_i^2+0=0+ \frac{1}{2}Kx^2\)

So,

⇒  \(K=\frac{mv_i^2}{x_2}\)

On substituting the values, we get

⇒       \(=\frac{1.2\times 5\times 5}{0.15\times 0.15}\)

⇒       \(=\frac{30}{0.0225}\)

⇒       \(=1333.33 \ N/m\)

Answer:Im doing that same quiz rn and i just put A

Explanation:

this is because EM energy is produced when electrically charged participles vibrate generating an electric filed and a magnetic field which sends out an EM wave.

i hope this helped

Answer:

With the increase in depth, age of layer increases.

Explanation:

According to the law of superposition, the layer of the Earth that is present in the deep is considered as the oldest layer while on the other hand, those layer which is present on the top of all layers is considered as youngest layer of earth. When we move from the top layer towards the bottom layer, the age of layer increases or in other words, when we move upward the age of the layer decreases so label the layers of earth on the basis of this phenomenon.

Given

The bending ability of a substance is recorded on the index of refraction.

To find

If the statement is true or false

Explanation

While a light is refracted to a denser medium then the light bents towards the normal and if it is refracted to a rarer medium, the light bends away from the normal

Thus the bending ability depends on the refractive index of the medium

Conclusion

The given statement is True

The people in the music industry still prefer analog music storage. Because analog devices record the music in its original form.

There are advantages to both digital and analog music. Even today, music connoisseurs debate the subject incessantly.

Understanding both recording methods can help you appreciate music more by providing you with a better understanding of playback depth. Analog and digital songs have different effects on playback,

But both can identify the various aspects of a song. In honor of music as a whole, we're diving into both and bringing out the best of each.

Hence people in the music industry still prefer analog music storage. Because analog devices record the music in its original form.

To learn more about analog device storage refer to the link;

https://brainly.com/question/11599772

Answer:

B

Explanation:

Answer:

3.68x10-15 J

Explanation:

I hope this is the right answer sorry if im wrong

To determine the mass of granite, we must first understand the definition of density. Density is defined as the amount of matter present in a substance per unit volume.

We use the formula: density = mass/volume to calculate the mass of a substance given its density and volume. To calculate the mass of 54.3 m³ of granite, we use the following steps:

Given Density of granite = 2700 kg/m³Given volume of granite = 54.3 m³Let us substitute the values in the formula of density:density = mass/volume Solving for mass, we get:mass = density × volume Substitute the given values of density and volume into the formula:mass = 2700 kg/m³ × 54.3 m³

The m³ unit in the volume cancels out, leaving us with kg as the unit for mass.

We then solve the equation to get the mass:mass = 146,610 kg

Therefore, the mass of 54.3 m³ of granite is 146,610 kg.

For such more question on density

https://brainly.com/question/26364788

#SPJ8

The time required for a sample of radioactive tritium to lose 76.0% of its activity is 24.6 years.

To calculate the time required for a sample of radioactive tritium to lose 76.0% of its activity, we can use the half-life formula. Tritium has a half-life of 12.3 years, which means that in 12.3 years, half of the initial amount of tritium will decay.

So, if we want to find out how long it takes for 76.0% of the tritium to decay, we can use the following formula:

time = (ln 2/ln(1/2)) x half-life x (ln(initial activity/final activity)).

Plugging in the values, we get time = (ln 2/ln(1/2)) x 12.3 x (ln(1/final activity)).

Since we want 76.0% of the activity to decay, we can set final activity = 0.24 (1-0.76), which gives us a time of approximately 24.6 years.

Learn more about tritium at https://brainly.com/question/31985379

#SPJ11

Answer:

\( \gamma \: dynamo \: converts \: the \: mechanical \: energy \: into \: electrical \: energy \: .\)

Explanation:

Hope it helps you :)))

Answer:

.

Explanation:

Answer:

C

Explanation:

The correct answer should be the micrometer.

The micrometer is an instrument that is capable of measuring the component of an object to very high precision. It is used to obtain accurate measurements in engineering.

In the case of the copper wire, the diameter of 0.3 mm was an approximation and a more accurate measure of the diameter would be obtained by using the micrometer.

The correct option is C.

Explanation:

answer is the 3rd law of motion

I hope it will be helpful for you

please mark as brainest answer

thank you

Answer:

d = 4217 m

Explanation:

Case 1.

Initial velocity, u = 0

Acceleration, a = 2.2 m/s²

Let d₁ is the distance in case 1. Using second equation of motion as follows :

\(d_1=ut+\dfrac{1}{2}a_1t_1^2\\\\\text{Here, u =0}\\\\d_1=\dfrac{1}{2}\times 2.2\times 10^2\\\\d_1=110\ m\)

Let d₂ in the distance in case 2. Using second equation of motion as follows :

\(d_2=ut+\dfrac{1}{2}a_2t_2^2\\\\\text{Here, u =0}\\\\d_2=\dfrac{1}{2}\times 1.5\times 74^2\\\\d_2=4107\ m\)

Total distance,

D = d₁ + d₂

D = 110 + 4107

D = 4217 m

Hence, the total distance covered is 4217 m.

The focal length of the objective lens is approximately -11856.5 cm, based on the given information.

To determine the focal length of the objective lens, we can use the formula for the total magnification of a compound microscope, given by:

Magnification = -(focal length of the objective lens / focal length of the eyepiece)

Given that the magnification is -4525 and the focal length of the eyepiece is 2.62 cm, we can substitute these values into the formula to solve for the focal length of the objective lens.

-4525 = -(focal length of the objective lens / 2.62)

By cross-multiplying and solving for the focal length of the objective lens, we get:

focal length of the objective lens = (-4525 * 2.62) cm

Finally, to find the numerical value, we calculate:

focal length of the objective lens ≈ -11856.5 cm

Therefore, the focal length of the objective lens is approximately -11856.5 cm.

For more such questions on length, click on:

https://brainly.com/question/29813582

#SPJ11

Answer:

36.5 kJ

Explanation:

Energy by machine = energy to machine × efficiency

E = 52.1 kJ × 0.70

E = 36.5 kJ

The situation in which a person would lose heat by conduction is a. Sitting on cold metal bleachers at a football game. Conduction occurs when heat is transferred through direct contact with a cooler object, in this case, the cold metal bleachers.

In situation a, sitting on cold metal bleachers at a football game, a person would lose heat by conduction. Conduction is the transfer of heat through direct contact between objects, so sitting on a cold metal surface would transfer heat from the body to the bleachers. In situation b, wearing wet clothing in windy weather, a person would lose heat by both conduction and convection. Convection is the transfer of heat through movement of air or fluid, so the wind would increase the rate of heat loss. In situation c, breathing, heat loss would occur through respiration, which is a form of evaporation. In situation d, going outside without a coat during a cold but calm day, a person would lose heat primarily through radiation and convection, but not as much through conduction.

Learn more about conduction here:-

https://brainly.com/question/31201773

#SPJ11

Answer:

35 m/s

Explanation:

vf = vo + at

vf = 15  +  5(4) = 35 m/s