A crane uses a single cable to lower a steel girder into place. The girder moves with constant speed. The cable tension does work WT and gravity does work WG. Which statement is true

Answers

Answer 1

Explanation:

Work done by a force is given by :

[tex]W=Fd\cos\theta[/tex]

Where

F is force, d is displacement and [tex]\theta[/tex] is the angle between F and d.

In this problem, a crane is moving in downward direction, the force gravity is in downward direction and the tension is in upward direction.

We know that if force and displacement is in same direction, work is positive while if force and displacement is in oposite direction, work is negative.

I would mean that, [tex]W_g[/tex] is positive, because gravity is parallel to the displacement and [tex]W_t[/tex] is negative, because the tension is opposite to the displacement.


Related Questions

Help me out on this?

Answers

I can’t see the problem

Which of the filling is a fossil fuel?

Answers

I need a picture to see what exactly this question is asking

Define reflection of sound?​

Answers

The reflection of sound is the movement of sound waves bouncing off of a surface and back into another direction, hope this helped :)

A
6. All other changeable factors that must
be kept the same to ensure a fair test
(what you keep the same).​

Answers

Answer:

a constant variable?

Explanation:

A constant variable is any aspect of an experiment that a researcher intentionally keeps unchanged throughout an experiment.

Experiments are always testing for measurable change, which is the dependent variable. You can also think of a dependent variable as the result obtained from an experiment. It is dependent on the change that occurs

3. A wye-connected load has a voltage of 480 V applied to it. What is the voltage dropped across each phase?

Answers

Answer:

[tex]E_s = 277.13V[/tex]

Explanation:

Given

[tex]Load\ Voltage = 480V[/tex]

Required

Determine the voltage dropped in each stage.

The relation between the load voltage and the voltage dropped in each stage is

[tex]E_l = E_s * \sqrt3[/tex]

Where

[tex]E_l = 480[/tex]

So, we have:

[tex]480 = E_s * \sqrt3[/tex]

Solve for [tex]E_s[/tex]

[tex]E_s = \frac{480}{\sqrt3}[/tex]

[tex]E_s = \frac{480}{1.73205080757}[/tex]

[tex]E_s = 277.128129211[/tex]

[tex]E_s = 277.13V[/tex]

Hence;

The voltage dropped at each phase is approximately 277.13V

A boat initially moving at 10 m/s accelerates at 2 m/s for 10 s. What is the velocity of the boat after 10 seconds?

Answers

Answer:

30 m/s

Explanation:

v = u + at

given that,

u = 10 m/s (initial speed)a = 2 m/s^2 t = 10sv =?(final speed)

v = 10 + ( 2 × 10)

v = 10 + 20

v = 30 m/s

The Earth's magnetic field is modeled as that of a bar magnet with the geographic poles being Magnetic poles of the bar magnet, Based on our definitions of Magnetic Poles, if you were to go to the Earth's Geographic North Pole, you would be at a Magnetic _______________ of the bar magnet.

Answers

Answer:

South pole

Explanation:

In a bar magnet, field lines go from the North Pole to the South Pole (outside the magnet).

As the earth magnetic field lines go from South Pole (geographic) to the North one, this means that the North pole (geographic) really behaves as a South Pole (magnetic).

what phase changes take place when you are adding energy to the substance

Answers

Answer:

During a phase change, a substance undergoes transition to a higher energy state when heat is added, or to a lower energy state when heat is removed. Heat is added to a substance during melting and vaporization. Latent heat is released by a substance during condensation and freezing. Explanation:

describe the energy conversion that occurs in a diesel engine

Answers

A diesel engine is a type of heat engine that uses the internal combustion process to convert the energy stored in the chemical bonds of the fuel into useful mechanical energy. ... First, the fuel reacts chemically (burns) and releases energy in the form of heat.

The boys are finally old enough to compete in the box car derby race at the local fair. They have been working on their cars since the conclusion of the race last year. One boy's car raced down the track and placed 2nd in his race. However, the other boy's car started well but half-way through the race a wheel came off and his car came to a complete stop. The boy was very disappointed and the other boy felt horrible for his friend. Which of the following graphs best represents the motion of boy's car that stopped?

Answers

i think it’s b because they both stumbled up a hole

What is the key for a successful relationship? and Why?

Answers

Answer:

communication, if you don't talk you'll never know what's going on.

Explanation:

Write a function to accept a vector of masses (m) from the user and gives the corresponding energy to them. Energy vector is the output of the program. Constant c is the speed of light which is 2.9979 x 108 m/s inside the function.

Answers

Answer:

Written in Python

def energyvector(mass):

    c = 2.9979 * 10**8

    energy = mass * c ** 2

    print(round(energy,2))

Explanation:

This line defines the function

def energyvector(mass):

This line initializes the speed of light

    c = 2.9979 * 10**8

This line calculates the corresponding energy

    energy = mass * c ** 2

This line prints the calculated energy

    print(round(energy,2))

Weight of a person's muscles, bones, tendons, and ligaments.
A. flexibility
B. lean mass
C. aerobic

Answers

I’m pretty sure it’s lean mass but let another guy answer you before you use mine

A sleigh is being pulled horizontally by a train of horses at a constant speed of 6.38 m/s. The magnitude of the normal force exerted by the snow-covered ground on the sleigh is 7.50 ✕ 103 N.
(a) If the coefficient of kinetic friction between the sleigh and the ground is 0.26, what is the magnitude of the kinetic friction force experienced by the sleigh?
N

(b) If the only other horizontal force exerted on the sleigh is due to the horses pulling the sleigh, what must be the magnitude of this force?
N

Answers

Answer:

(a). The kinetic friction force is 1950 N.

(b). The magnitude of force will be equal of friction force

Explanation:

Given that,

Constant speed = 6.38 m/s

Force [tex]F=7.50\times10^{3}\ N[/tex]

Kinetic friction = 0.26

(a). We need to calculate the friction force

Using formula of friction force

[tex]f_{k}=\mu F_{N}[/tex]

Put the value into the formula

[tex]f_{k}=0.26\times7.50\times10^{3}[/tex]

[tex]f_{k}=1950\ N[/tex]

(b). If the only other horizontal force exerted on the sleigh is due to the horses pulling the sleigh,

We need to calculate the magnitude of this force

According to given data,

The same force will be applied to keep constant velocity.

Hence, (a). The kinetic friction force is 1950 N.

(b). The magnitude of force will be equal of friction force.

(a). The kinetic friction force is 1950 N.

(b). The magnitude of force will be equal of friction force

The calculation is as follows;

a. The magnitude of the kinetic friction force experienced by the sleigh is

[tex]= 0.76 \times 7.50 \times 10^3[/tex]

= 1950 N

b. It should be equivalent to the friction force.

Learn more: https://brainly.com/question/24908711?referrer=searchResults

Question 4
Which of the following is unique for any given element?
O the mass of a neutron
o the number of neutrons
o the charge on the electons
O the number of protons

Answers

the number of protons

it's unique for any element because it's determined by the atomic number and no two elements have the same atomic number

How long would it take you to walk 3,962 km from New York to Los
Angeles?

Answers

Answer:

913 hours ur welcome :)

HELP PLEASE!!!
If we have a sample of silicon (Si) atoms that has 14 protons, 14 electrons, and 18 neutrons
What is the name of this specific silicon isotope?
si-14
si-32
si-46
si-153

Answers

Answer:

It is si-32

Explanation:

Answer:

silicon-32

Explanation:

just took the quiz and got it right

Help me Please!!!!!!!

Answers

The speed is equal to the area under the line up to the point where t .=15 s.
Do find the area of the triangle and that if the rectangle and add them together.
The area of the triangle is 25 and the rectangle is also 25 so the speed is 50 m/s

What do mammoths and tigers need energy for

Answers

Muscles
.............

Work Done by a Varying Force 06 Work and Energy
w of Energy
100%
2.) The force required to stretch a spring by 1 m from its unstretched length is
150 N. What is the force required to stretch the spring by 3 m?

A. 600 N

B. 450 N

C. 300 N

D. 200 N

Answers

Answer:

B. 450 N

Explanation:

Use Hooke's law:

F = kx

150 N = k (1 m)

k = 150 N/m

F = kx

F = (150 N/m) (3 m)

F = 450 N

A car which is traveling at a velocity of 15 m/s undergoes an acceleration of 6.5 m/s2 over a distance of 340 m. How fast is it going after that acceleration?

Answers

Answer:68.15m/s

Explanation:

Given:

v₁=15m/s

a=6.5m/s²

v₁=?

x=340m

Formula:

v₁²=v₁²+2a (x)

Set up:

=[tex]\sqrt{15m/s} ^{2} +2(6.5m/s^2)(340m)[/tex]

Solution:68.15m/s

Your TV has a resistance of 10 ohms and a wall voltage of 120 V. How much current and power does it use

Answers

Answer:

Current used is 12 ampere.

Power is 1440 watts.

Explanation:

To find the current used by the TV.

Current (I) = voltage/resistance

Current= 120/10

Current is 12Ampere.

To get power used by the TV,

Power = voltage × current.

= 120× 12

Power = 1440 watts.

Compare and contrast the CONFLICT (choose one) in the short story you read with the elements appearing in The Watsons Go to Birmingham—1963. Explain how they are similar or different in a few sentences.

Answers

Answer:

they were in two places in flint and Birmingham and in Birmingham it is hot but flint of cold the Simi is they both have Sunday school for Joetta

Explanation:

use in your own words teachers know when your not trust me.

-. What is the acceleration of 4 kg trolling bag pulled by a girl with a
force of 3 N?

Answers

Answer:

Acceleration(a) = 0.75 m/s²

Explanation:

Given:

Force(F) = 3 N

Mass of thing(m) = 4 kg

Find:

Acceleration(a)

Computation:

Force(F) = ma

3 = (4)(a)

Acceleration(a) = 3/4

Acceleration(a) = 0.75 m/s²

A 75 Kg skateboarder is riding downhill, exerting 25 N. What is their acceleration?

Answers

Answer:

[tex]a=0.33\frac{m}{s^2}[/tex]

Explanation:

Hello.

In this case, since the force is defined in terms of the mass and acceleration as follows:

[tex]F=ma[/tex]

Given the force and the mass, we can compute the acceleration as shown below:

[tex]a=\frac{F}{m}=\frac{25N}{75kg}=\frac{25kg\frac{m}{s^2} }{75kg}\\ \\a=0.33\frac{m}{s^2}[/tex]

Best regards.

In a mattress test, you drop a 7.0 kg bowling ball from a height of 1.5 m above a mattress, which as a result compresses 15 cm as the ball comes to a stop. (a) What is the kinetic energy of the ball just bef

Answers

Answer:

(a) The kinetic energy of the bowling ball just before it hits the matress is 102.974 joules.

(b) The work done by the gravitational force of Earth on bowling ball during the first part of the fall is 102.974 joules.

(c) Work done by gravitational force on bowling ball when mattress is compressed is 10.298 joules.

(d) The work done by the mattress on the bowling ball is 113.272 joules.

Explanation:

The statement is incomplete. The complete question is:

In a mattress test, you drop a 7.0 kg bowling ball from a height of 1.5 m above a mattress, which as a result compresses 15 cm as the ball comes to a stop.

(a) What is the kinetic energy of the ball just before it hits the mattress?  

(b) How much work does the gravitational force of the earth do on the ball as it falls, for the first part of the fall (from the moment you drop it to just before it hits the mattress)?  

(c) How much work does the gravitational force do on the ball while it is compressing the mattress?

(d) How much work does the mattress do on the ball? (You’ll need to use the results of parts (a) and (c)

(a) Based on the Principle of Energy Conservation, we know that ball-earth system is conservative, so that kinetic energy is increased at the expense of gravitational potential energy as ball falls:

[tex]K_{1}+U_{g,1} = K_{2}+U_{g,2}[/tex] (Eq. 1)

Where:

[tex]K_{1}[/tex], [tex]K_{2}[/tex] - Kinetic energies at top and bottom, measured in joules.

[tex]U_{g,1}[/tex], [tex]U_{g,2}[/tex] - Gravitational potential energies at top and bottom, measured in joules.

Now we expand the expression by definition of gravitational potential energy:

[tex]U_{g,1}-U_{g,2} = K_{2}-K_{1}[/tex]

[tex]K_{2}= m\cdot g \cdot (z_{1}-z_{2})+K_{1}[/tex] (Eq. 1b)

Where:

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

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

[tex]z_{1}[/tex], [tex]z_{2}[/tex] - Initial and final heights of the bowling ball, measured in meters.

If we know that [tex]m = 7\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], [tex]z_{1}= 1.5\,m[/tex], [tex]z_{2} = 0\,m[/tex] and [tex]K_{1} = 0\,J[/tex], the kinetic energy of the ball just before it hits the matress:

[tex]K_{2} = (7\,kg)\cdot \left(9.807\,\frac{m}{s^{2}}\right)\cdot (1.5\,m-0\,m)+0\,m[/tex]

[tex]K_{2} = 102.974\,J[/tex]

The kinetic energy of the bowling ball just before it hits the matress is 102.974 joules.

(b) The gravitational work done by the gravitational force of Earth ([tex]\Delta W[/tex]), measured in joules, is obtained by Work-Energy Theorem and definition of gravitational potential energy:

[tex]\Delta W = U_{g,1}-U_{g,2}[/tex]

[tex]\Delta W = m\cdot g\cdot (z_{1}-z_{2})[/tex] (Eq. 2)

If we know that [tex]m = 7\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], [tex]z_{1}= 1.5\,m[/tex] and [tex]z_{2} = 0\,m[/tex], then the gravitational work done is:

[tex]\Delta W = (7\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)\cdot (1.5\,m-0\,m)[/tex]

[tex]\Delta W = 102.974\,J[/tex]

The work done by the gravitational force of Earth on bowling ball during the first part of the fall is 102.974 joules.

(c) The work done by the gravitational force of Earth while the bowling when mattress is compressed is determined by Work-Energy Theorem and definition of gravitational potential energy:

[tex]\Delta W = U_{g,2}-U_{g,3}[/tex]

Where [tex]U_{g,3}[/tex] is the gravitational potential energy of the bowling ball when mattress in compressed, measured in joules.

[tex]\Delta W = m\cdot g \cdot (z_{2}-z_{3})[/tex]

Where [tex]z_{3}[/tex] is the height of the ball when mattress is compressed, measured in meters.

If we know that [tex]m = 7\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], [tex]z_{2}= 0\,m[/tex] and [tex]z_{3} = -0.15\,m[/tex], the work done is:

[tex]\Delta W = (7\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)\cdot [0\,m-(-0.15\,m)][/tex]

[tex]\Delta W = 10.298\,J[/tex]

Work done by gravitational force on bowling ball when mattress is compressed is 10.298 joules.

(d) The work done by the mattress on the ball equals the sum of kinetic energy just before mattress compression and the work done by the gravitational force when mattress is compressed:

[tex]\Delta W' = K_{2}+\Delta W[/tex]

([tex]K_{2} = 102.974\,J[/tex], [tex]\Delta W = 10.298\,W[/tex])

[tex]\Delta W' = 113.272\,J[/tex]

The work done by the mattress on the bowling ball is 113.272 joules.

What's the difference between an open cluster and a globular cluster

Answers

An open cluster is a group of up to a few thousand stars that were formed from the same giant molecular cloud, and are still loosely gravitationally bound to each other. In contrast, globular clusters are very tightly bound by gravity. ... Open clusters are very important objects in the study of stellar evolution.

Consider a particle of mass m which can move freely along the x axis from -a/2 to a/2, but which is strictly prohibited from being found outside this region. The wave function of the particle within the allowed region is

Answers

Answer:

  φ = B sin (2π n/a   x)

Explanation:

In quantum mechanics when a particle moves freely it implies that the potential is zero (V = 0), so its wave function is

     φ = A cos kx + B sin kx

we must place the boundary conditions to determine the value of the constants A and B.

In our case we are told that the particle cannot be outside the boundary given by x = ± a / 2

therefore we must make the cosine part zero, for this the constant A = 0, the wave function remains

    φ = B sin kx

the wave vector is

      k = 2π /λ

now let's adjust the period, in the border fi = 0 therefore the sine function must be zero

         φ (a /2) = 0

          0 = A sin (2π/λ  a/2)

therefore the sine argument is

          2π /λ   a/2 = n π

          λ= a / n

we substitute

          φ = B sin (2π n/a   x)

A student uses a microwave oven to heat a meal. The wavelength of the radiation is 8.97 cm. What is the energy of one photon of this microwave radiation? Multiply the answer you get by 1025 to be able to input a number more easily into canvas. Enter to 2 decimal places.

Answers

Answer:

The energy of one photon is 2.21x10⁻²⁴ J. Multiplied by 10²⁵ is 22.10 J.

         

Explanation:  

The energy (E) of a photon is:

[tex] E = h\frac{c}{\lambda} [/tex]

Where:

h: is the Planck's constant = 6.62x10⁻³⁴ J.s

λ: is the wavelength of the radiation = 8.97 cm

c: is the speed of light = 3.00x10⁸ m/s

[tex] E = h\frac{c}{\lambda} = 6.62 \cdot 10^{-34} J.s\frac{3.00\cdot 10^{8} m/s}{8.97 \cdot 10^{-2} m} = 2.21 \cdot 10^{-24} J [/tex]

Hence, the energy of one photon is 2.21x10⁻²⁴ J.

Now, if we multiply the answer by 10²⁵ we have:

[tex] E = 2.21 \cdot 10^{-24} J \cdot 10^{25} = 22.10 J [/tex]

I hope it helps you!

The energy of one photon is 2.21x10⁻²⁴ J. Multiplied by 10²⁵ is 22.10 J.

Calculation of energy:

We know that

[tex]E = h\frac{c}{\lambda}[/tex]

Here

h be the Planck's constant = 6.62x10⁻³⁴ J.s

λ be the wavelength of the radiation = 8.97 cm

c be the speed of light = 3.00x10⁸ m/s

Now

Here we need to multiply the answer 10^25 so that the correct answer could come.

[tex]E = 6.62.10^{-34} \frac{3.00.10^{8}}{8.97.10^{-2}}[/tex]

=  2.21x10⁻²⁴ J.

= 22.10 J.

Hence, the energy of one photon is 2.21x10⁻²⁴ J. Multiplied by 10²⁵ is 22.10 J.

learn more about energy here; https://brainly.com/question/24719731

the radius of the earth social

Answers

6,371km is the radius of the earth
Other Questions
PLS ANSWER WILL GIVE BRAINLIEST!! PLSS!In the play, the _____________of events is changed. But many of the characters are the same. Nonsense,________________, and distortion of time and space are themes in the novels as well as the play. This is on Alice in Wonderland and Through The Looking Glass. Please make sure you understand the text before answering. How is democracy in ancient Athens different from the democracy in America today? *1) Ancient Athens's democracy was a constitutional democracy 2)Ancient Athens's democracy was a religious democracy.3) Ancient Athens's democracy was a direct democracy. He was more depressed than ever as he drove on by himself. The late afternoon had grown hot and sultry and the country had flattened out. Deep in the sky a storm was preparing very slowly and without thunder as if it meant to drain every drop of air from the earth before it broke. There were times when Mr. Shiftlet preferred not to be alone. He felt too that a man with a car had a responsibility to others and he kept his eye out for a hitch-hiker. Occasionally he saw a sign that warned: "Drive carefully. The life you save may be your own." Which statement most accurately represents the excerpt's larger idea? the equation 3x^2-6x=8 is rewritten in a form of 3(x-p)^2+q=0. Which study strategy would be most effective for an extravert? Which one is the correct one? This activity is important because any business that offers multiple product lines to multiple market segments is faced with the task of making the product/market decisions and prioritizing those decisions. Products and market segments that are growing quickly and are very profitable should get more attention and resources than a product and market segment that does not show as much potential. Once a marketing manager creates a market-product grid, they must select which segments to target. To do this, the marketing manager should use several criteria in assessing the different segments. Those criteria include: market size, expected growth, competitive position, cost of reaching the segment, and the compatibility with the organization's objectives and resources. The goal of this exercise is to demonstrate your understanding of the market-product development process by analyzing a gift shop's markets and products. Read the case below and then answer the questions that follow as you consider its markets and product offerings. A small local gift shop recently marked its 25th anniversary of being in business. Over that time, the owners have continually changed the products sold in its store to reflect changes in the market. From the early days of selling small gift-type items such as figurines and collectibles, the store now offers a more eclectic mix of merchandise that includes Vera Bradley purses and inexpensive jewelry, as well as items that could be classified as "gift-type" products and merchandise that is best described as "collectibles." However, the demographics of the store's market, as well as the needs of that market, seem to be changing. There has been an influx of younger customers (20s and 30s) into the area, which has brought the average age of the area down by 9.8 years. This rapidly growing segment doesn't seem interested in buying the same collectibles that their parents bought. Many older residents (60s and 70s) have been leaving the area for retirement. The older customers are still buying the collectibles, but are also buying gifts for children and grandchildren for holidays and special occasions. Indeed, while sales of merchandise aimed at the younger customers have grown 30 percent, sales to the older crowd have been flat. And the younger group has now passed the older segment in terms of the size of the population. While there are other stores in the area selling similar merchandise, this gift shop has managed to get an exclusive on the Vera Bradley line, which has been popular with the younger customers. The owners of the gift shop are considering which market segment should be the focus of their attention and limited resources. This is an especially critical decision because of the limited space in the store and the need to add fixtures for carrying some of the collectible items that are coming on the market. Based on the limited information in the case, which market segment is larger? a) the over-80 segment b) all segments are the same size c) the 60s and 70s segment d) the 20s and 30s segment why is it important to understand plant physiology in crop/plant production and productivity?in your discussion make sure that you mention related fields/areas in agriculture which specifically require a background of plant physiology What is the range of the function shown in this table? 3 4 5 6 y4 4 2 5 A. (3, 4), (4, 4), (5, 2), {6, 5{ B. {3,4,5,6} C. {3, 4} D. {2,4,5} Polytheism is the belief in one all powerful, just and personal god True or False ? What led to the rising number of enslaved people in Mississippi between 1800 and 1600A. Increasing demand for fitting overseas B. Increasing demand for manufactured goodsC. Improved productivity in the states factories D. Improved working conditions among field hands Find the slope of f(x)=5x-4 I need help with this please The Odyssey: Theme Development, Part 6What can a reader who knows the steps of the hero quest predict about the rest of the Odyssey? Check all that apply. Which of the following was NOT a Roman advance in architecture?The use of concrete to use as building material.The use of arches and columns to enhance support for structures.The creation of domes to roof large spaces.The creation of the flying buttress to increase space and decrease building material. Q SearchGeneralPostsFilesClass Notebook Assignments GradesSync Copy linkDownloadOpen in SharePointGeneral > Class MaterialsSummarisingLevel ...NameModifiedWAn Angel in Disguise.docxOctober 19 Which is the closest antonym for the word biased? A: dishonest B: enthusiastic C: neutral D: apologetic PLS I NEED THIS ASAP 100 POINT ---------The shoe stores clerks are paid on commission. If the clerk receives a 12% commission on total purchase amounts before tax is applied, how much would the commission be for Isaacs purchase with and without a coupon? 100 POINTS Polly stacked the tins from five boxes of cat food onto an empty shelf in a supermarket. There were 15 tins of cat food in each box. At the end of the week there were 20 tins left on the shelf. The rest of the tins had been sold. Write the number of boxes of cat food that had been sold, as: (a) A mixed number (b) An improper fraction -5(2x+9)? simplify the expressions by disturbing the negatives and combining like terms