A box having a weight of 8 lb is moving around in a circle of radius rA = 2 ft with a speed of (vA)1 = 5 ft/s while connected to the end of a rope. If the rope is pulled inward with a constant speed of vr = 4 ft/s, determine the speed of the box at the instant rB = 1 ft. How much work is done after pulling in the rope from A to B? Neglect friction and the size of the box

Answers

Answer 1

Answer:

W = 1.875 J

Explanation:

For this exercise let's use the relationship between work and kinetic energy

          W = ΔK

The kinetic energy of rotational motion is

         K₀ = ½ I w²

we can assume that the box is small, so it can be treated as a point object, with moment of inertia

          I = m rₐ²

angular and linear velocity are related

          v = w r

          w = v / r

we substitute in the equation, for point A

         K₀ = ½ (m rₐ²) (v / rₐ)²

         K₀ = ½ m v²

For the final point B, as the system is isolated the angular momentum is conserved

initial        L₀ = Io wo

final          L_f = I_f w_f

                L₀ = L_f

                 I₀ w₀ = I_f w_f

               

                (m rₐ²) w₀ = (m  [tex]r_{b} ^2[/tex]) w_f

                 w_f = (rₐ/r_b)² w₀

with this value we find the final kinetic energy

         K_f = ½ I_f w_f²

         K_f = ½ (m [tex]r_{b}^2[/tex]) ( (rₐ / r_b)²  w₀) ²

         K_f = ½ m [tex]\frac{r_a^4}{r_b^2} \ w_o^2[/tex]

 

we substitute in the realcion of work

          W = K_f - K₀

          W = ½ m  [tex]( \( \frac {r_a^2 }{r_b} )^2[/tex] w₀² - ½ m v²

          W = ½ m  [tex]\frac{r_a^4}{r_b^2} ( \frac{v}{r_a} ) ^2[/tex] - ½ m v²

           W = ½ m [tex]\frac{r_a^2}{r_b^2} \ v^2[/tex] - ½ m v2

          W = ½ m v² (([tex]( \ (\frac{r_a}{r_b})^2 -1)[/tex]

let's calculate

           W = ½ ( [tex]\frac{8}{32}[/tex] ) 5 ((2/1)² -1)

           W = 0.625 (3)

           W = 1.875 J

         


Related Questions

Help please. Question about a potential energy.

Answers

P=m*g*h. So this implies that 130*10*0.200=260J. Bear in mind that g is constant.

When you cool a gas, how does this affect the de Broglie wavelength of the gas atoms? When you cool a gas, how does this affect the de Broglie wavelength of the gas atoms? Being cooled, the gas atoms slow down so that their de Broglie wavelength will increase. Being cooled, the gas atoms slow down so that their de Broglie wavelength will decrease. The de Broglie wavelength will remain the same because it does not depend on temperature.

Answers

Answer:

The de Broglie wavelength will remain the same because it does not depend on temperature.

Explanation:

de Broglie wavelength of a particle is independent of the temperature and hence the properties of emitted particle such as photoelectric effect, radioactive radiation etc. does not depend on the temperature.

Also, until unless the kinetic energy of a moving particle is not driven by the

thermal energy, the de Broglie wavelength  is independent of the temperature

Explain why your image never disappears and never flips over as you bring the convex mirror
close to your eye.

Answers

Explanation:

When you get closer to the mirror than the focal point a virtual image is formed behind the mirror and this image is not inverted. That's why the image flips as you get closer. ... With a virtual image the light rays never come to a focus so there is no place you can put a piece of paper to see the image.

Pls quickly brainliest to the first to anwser

Answers

Answer:

8m/s^2

Explanation:

hope it helps........

Explanation:

you're supposed to know the formula of acceleration which is velocity of a time then you can solve the question


In an application, Germanium is
made p-type material by adding
Indium. The rate of adding is one
indium atom
per
3 Germanium
atom. Assume donor density to be
zero and ni = 6.2 Cubic
metre at room temperature.
Determine the value
of
the
aceeptor atom density​

Answers

Answer:

produce electronics

Explanation:

The uses of Germanium are recorded beneath: Germanium's principle use is to deliver strong state hardware, semiconductors and fiber optic frameworks. As a phosphor in fluorescent lights.

A 6.47 micro-coloumb particle moves through a region of space where an electric field of magnitude 1300 N/C points in the positive x direction, and a magnetic field of magnitude 1.33 T points in the positive z direction. If the net force acting on the particle is 6.27E^-3 N in the positive x direction>

Required:
Calculate the magnitude of the particle's velocity. Assume the particle's velocity is in the xy plane.

Answers

Answer:

v = 248.8 m/s

Explanation:

Given that,

Charge, q = [tex]6.47\ \mu C[/tex]

Electric field, E = 1300 N/C

Magnetic field, B =1.33 T

The force acting on the particle, [tex]F=6.27\times 10^{-3}\ N[/tex]

We need to find the magnitude of the particle's velocity. The net force on the particle is given by :

[tex]F=qE+qvB\\\\6.27\times 10^{-3}=6.47\times 10^{-6}\times 1300+6.47\times 10^{-6}\times 1.33v\\\\6.27\times 10^{-3}-6.47\times 10^{-6}\times 1300=6.47\times 10^{-6}\times 1.33v\\\\-0.002141=6.47\times 10^{-6}\times 1.33v\\\\v=\dfrac{0.002141}{6.47\times 10^{-6}\times 1.33}\\\\v=248.8\ m/s[/tex]

So, the magnitude of the particle's velocity is 248.8 m/s.

Two identical springs of equilibrium length L and spring stiffness kare attached to opposite sides of a block of mass Mto two parallel walls a distance Dfrom each other, where D< 2L. The block moves horizontally along a rail with no friction. At what positions along the rail will the block be stable

Answers

Answer:

Hydraulic fracturing

Explanation:

Calculate the terminal velocity of
the following nain drops faning
through air (a) one with a diameter
of 0.3cm 6 one with a a diameter
of o. Olm. Take the density of
water to be looo Kym3 and the
eis cosity of air to be ixlos pas.
The buoyancy effect of the air
may be ignored)​

Answers

I’m pretty sure it’s a

One hazard of space travel is debris left by previous missions. There are several thousand objects orbiting Earth that are large enough to be detected by radar, but there are far greater numbers of very small objects, such as flakes of paint. The force exerted by a 0.100-mg chip of paint that strikes a spacecraft window at a relative speed of 4.00 x 103 m/s, given the collision lasts 6.00 x 10-8 s is Fill input: x 106 N.

Answers

Answer:

The correct answer is "6666.67 N".

Explanation:

The given values are:

Mass,

m = 0.100

Relative speed,

v = 4.00 x 10³

time,

t = 6.00 x 10⁻⁸

As we know,

⇒  [tex]F=m(\frac{\Delta v}{\Delta t} )[/tex]

On substituting the given values, we get

⇒      [tex]=0.100\times 10^{-6}(\frac{4\times 10^3}{6\times 10^{-8}} )[/tex]

⇒      [tex]=6666.67 \ N[/tex]

why entrepreneurs should not be a wild risk taker?​

Answers

Explanation:

Entrepreneurs are not wild risk takers but are instead calculating risk takers. They appear to be risk takers because they see the market differently than the rest of us do. 3. ... Entrepreneurs tend to be optimistic about their chances for success, and usually their optimism is based in reality.

a constant force of magnitude F=45 N and making an angle of 30 to the horizontal is applied on a stationary block placed on the floor over a distance of 8 m. the work done by the force

Answers

The work done by the force on the block is approximately 311.2 Joules.

To calculate the work done by the constant force of magnitude F = 45 N over a distance of 8 m at an angle of 30 degrees to the horizontal, we need to find the component of the force that acts parallel to the displacement.

The horizontal component of the force can be calculated using trigonometry:

F_horizontal = F * cos(angle)

            = 45 N * cos(30 degrees)

            = 45 N * (√3 / 2)

            ≈ 38.9 N

Now, we can calculate the work done by the force using the equation:

Work = Force * Distance * cos(theta)

where theta is the angle between the force and the displacement.

Work = F_horizontal * Distance * cos(0)

     = 38.9 N * 8 m * cos(0)

     = 38.9 N * 8 m

     = 311.2 Joules

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the higher the objects " ? ", the more kinetic energy

Answers

ANSWER: friction


STEP BY STEP EXPLANATION:

answer asap!!! i suck at acceleration

Answers

Answer: 2.67

Explanation: it said he went from 0 to 8 in 3 seconds so if we divide eight By three we get 2.67 rounded to the nearest hundredth so you accelerated that 2.67 m/s

Two experiments are performed on an object to determine how much the object resists a change in its state of motion while at rest and while in motion. In the first experiment, the object is pushed with a constant known force along a horizontal surface. There is negligible friction between the surface and the object. A motion sensor is used to measure the speed of the object as it is pushed. In a second experiment, the object is tied to a string and pulled upward with a constant known force, and a motion sensor is used to measure the speed of the object as it is pulled upward. The student uses the data collected from the motion sensor to determine the mass of the object in both experiments.

Required:
What classifies the type of mass that was determined in each experiment?

Answers

Answer:

In the first experiment, the mass is inertial mass and in the second experiment, the mass is a gravitational mass.

Explanation:

It is given that a student performs two types of experiment to see how change in its resistance while in the state of motion and in rest.

In the first experiment, an object is pushed with a force against a horizontal surface and the speed is measured using a sensor. Here, work is done against the inertia of the object as it is pushed from rest. So the mass is inertial mass.

In the second experiment, an object is pushed or thrown upwards with a force and speed is measured. Here, the mass is gravitational mass as the work done in the second experiment is against the gravity or against the weight of the object.

In the first experiment, the mass is inertial mass and in the second experiment, the mass is a gravitational mass.

As per the given problem, the student performs two types of experiment to see how change in its resistance while in the state of motion and in rest.

In the first experiment, an object is pushed with a force against a horizontal surface and the speed is measured using a sensor. Here, work is done against the inertia of the object as it is pushed from rest. So the mass is inertial mass. In the second experiment, an object is pushed or thrown upwards with a force and speed is measured. Here, the mass is gravitational mass as the work done in the second experiment is against the gravity or against the weight of the object.

Thus, we can conclude that the in the first experiment, the mass is inertial mass and in the second experiment, the mass is a gravitational mass.

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Your eyes form upside-down images, which are then flipped right-side-up by our brains.


True
False

Answers

Answer:

I believe it is true, but our brains don’t do it, I think it is the lenses in our eyes that do it. I might be wrong tho

Explanation:

Answer:

Yes it is true that our eyes form upside-down images, which are flipped right-side-up by our brain.

Help me please it’s due right now review question help

Answers

Answer:

M.E = mgh

given, m=400g = 400/1000=0.4kg

h=1.75m

g=9.81m/s²

M.E =0.4×9.81×1.75

=6.867J

A hand dryer blows heated air downwards out of the exit duct at a velocity of 4 m/s. The temperature and density of the ambient air at the inlet are 15 C and 1.23 kg/m3, while at the outlet it has temperature 35 C and density 1.15 kg/m3 The blower power is 10.0 W and the heater power is 715 W. Consider the inlet to be at the large mass of ambient air which has negligible velocity.
a) What is the pressure at the outlet? 4 m/s, 35 C
b) You will be applying the energy equation. Why can you ignore any height differences in this situation?
c) If the specific heat of air C-1000 J/(kg K), where Δυ-C Δ T, find the change in internal energy per unit mass from the inlet to outlet.
d) Find the mass flow rate through the dryer.
e) What is the power loss in the system?
f) What is the loss in the system?
g) What is the head loss in the system?
h) What is the total loss coefficient of the system, referred to the outlet velocity?
i) If there were no heater, would the temperature of gas at the outlet be higher, the same, or lower than the inlet? Explain why.

Answers

Answer:

nzkdjdksishdjsdjjdjnzkskejeoueeuieeoyrie ryrhdhcksodopdncndnszdkhfoeosheiwuef wokxkzdkjdoeehxjbxbdkeiehdhdhddjjddjdhhdhdhhhjdhfjdjjfjddhdheudiwiehdbejwowud

Explanation:

isos

Which device converts electric energy into mechanical energy?
O A. An electromagnet
O B. A motor
O C. A transformer
O D. A generator

Answers

Answer:

B motor

Explanation:

a disk of a radius 50 cm rotates at a constant rate of 100 rpm. what distance in meters will a point on the outside rim travel during 30 seconds of rotation?​

Answers

50π m ≈ 157 m
Explanation:
100 rev/min (2π rad/rev) / (60 sec/min) = 3⅓π rad/s
d = ωrt = 3⅓π(0.50)(30) = 50π m ≈ 157 m

6) Which of the following describes a good team member?
A) She is willing to compromise.
B) He is aggressive.
C) She is stubborn.
D) He is conceited.

Answers

A she is willing to compromise because she is okay with having to sacrifice what she wants to make it work

Answer: A

Explanation:

Because someone who is aggressive, stubborn, or proud of theirselves are more likely to think they're above everyone else and be a bully. However someone who is willing to compromise is better since you can generally make everyone happy that way

HOPE THIS HELPS ^^

what is the stress in a steel wire that is 5m long and 0.04cm squared in cross section If the wire bears a load of 20kg?

Answers

Answer:

Explanation:

stress = ?

length =5 m

area of cross section = 0.04 cm or 0.0004m

force = 20 × 10 = 200 N ( w = mg) g = 10

formula : stress = force / cross-sectional area

stress = 200 / 0.0004

stress = 500,000 Nm^-2

The data table for the decomposition reaction of hydrogen peroxide H2 O2 shows how the reaction rate changes over time which statement describes the conclusion you can sharpen the table

Answers

The data table for the decomposition reaction of hydrogen peroxide H₂ O₂ shows down over time as the reactant rate get used up.

What is rate, reaction and rate of reaction?

Rate- The rate of a particular chemical reaction is calculated by dividing the rate of change in a reactant's or product's concentration by the coefficient from the given balanced equation.

Reactions- They are defined as the change of a chemical substance into an innovative substance through the formation and breaking of bonds among distinct atoms.

Rate of reaction- It is defined as the ratio of the increase in product concentration per unit time to the decrease in reactant concentration per unit time. The rate of reaction varies greatly.

It can be seen that with the concentration, the rate of decomposition is also decreased. Generally, it is found that as per hour concentration and rate of decomposition decreases as well.

Therefore, (A) option is the correct answer.

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You are watching a s Saturday morning cartoon concerning a jungle hero called George of the Jungle. George attempts to save a friend, an ape named Ape, from a stampeding herd of wildebeests. Ape is at the base of a tall tree which has a vine attached to its top. George is in another tree holding the other end of the vine. George plans to swing down from the tree, grab Ape at the bottom of the swing, and continue up to safety on a ledge which is half of George's initial height in the tree. Assuming that Ape weights the same as George, will they successfully make it to the top of the ledge? If you believe they do, how high a ledge could they make it to? If you disagree, suggest what could be done for George to save Ape.​

Answers

Answer:

I don't think so because if Ape was the same weight as george I don't

think he can hold him but maybe so let's say he could hold his own ape then Yes I think he could make it to the ledge Now I think they could make it to the ledge which was half the size.

Sorry if this sounded weird English is my 2nd language Oh and if this helped please give brainiest thank you <3

A bird is flying directly toward a stationary bird-watcher and emits a frequency of 1490 Hz. The bird-watcher, however, hears a frequency of 1505 Hz. What is the speed of the bird, expressed as a percentage of the speed of sound

Answers

Answer:

The speed of the bird is 1.00% of the speed of sound.

Explanation:

The speed of the bird can be found by using the Doppler equation:

[tex] f = f_{0}(\frac{v - v_{r}}{v - v_{s}}) [/tex]

Where:

v: is the speed of sound = 343 m/s

f₀: is the frequency emitted = 1490 Hz

f: is the frequency observed = 1505 Hz

[tex]v_{r}[/tex]: is the speed of the receiver = 0 (it is stationary)

[tex]v_{s}[/tex]: is the speed of the source =?

The minus sign of [tex]v_{s}[/tex] is because the source is moving towards the receiver.

By solving the above equation for [tex]v_{s}[/tex] we have:

[tex] v_{s} = v - \frac{f_{0}*v}{f} = 343 - \frac{1490*343}{1505} = 3.42 m/s [/tex]

The above speed in terms of the speed of sound is:

[tex]\% v_{s} = \frac{3.42}{343}\times 100 = 1.00 \%[/tex]

Therefore, the speed of the bird is 1.00% of the speed of sound.  

I hope it helps you!

During the Dust Bowl in the 1930s, there were huge dust storms caused by drought and wind. Farm areas all across the Midwest were affected by erosion. Many farmers lost the crops on which they depended to make a living and support their families.
How can farmers prevent soil erosion on their farms? Choose the two that apply.

A. Leave roots in the soil after harvesting.
B. Plant trees around the fields to block wind.
C. Harvest all the crops on the farm at once.
D. Pull up the entire plant when they harvest crops.

Answers

A. Leave roots in the soil after harvesting
B. Plant trees around the fields to block wind

Batteries are not perfect. They can't deliver infinite current. As the current load on a battery gets larger, the voltage output gets smaller.

a. True
b. False

Answers

True Im typing this for charater limit

please help me !
1. Suppose that the temperature drops 25 degrees overnight. When you get into your car the next morning, your low tire pressure light comes on. Explain, in terms of the ideal gas law, why this happened (assume air is an ideal gas). (10 points)

Answers

Answer:

The drop in temperature overnight causes a decrease in the average kinetic energy of the air molecules inside the tires. According to the ideal gas law, this leads to a decrease in tire pressure. The low tire pressure light in vehicles is triggered when the pressure falls below a certain threshold, alerting the driver to check and adjust the tire pressure.

Explanation:

The ideal gas law, represented by the equation PV = nRT, relates the pressure (P), volume (V), number of moles (n), and temperature (T) of an ideal gas. In this case, we can analyze how the drop in temperature affects the tire pressure.

When the temperature drops, according to the ideal gas law, the pressure of a gas will decrease if the volume and the number of moles remain constant. This is because the decrease in temperature causes a decrease in the average kinetic energy of the gas particles, leading to less frequent and less forceful collisions with the tire walls, resulting in a decrease in pressure.

In the context of the tire pressure, the air inside the tires behaves as an ideal gas. When the temperature drops overnight, the air inside the tires also cools down, causing a decrease in its temperature. As a result, the average kinetic energy of the air molecules decreases, leading to a decrease in pressure inside the tires.

The low tire pressure light comes on as a result of this drop in pressure. The tire pressure monitoring system in modern vehicles is designed to detect significant deviations from the recommended tire pressure. When the pressure drops below a certain threshold, typically due to temperature changes or a puncture, the light is triggered to alert the driver to check and adjust the tire pressure.

Therefore, the drop in temperature overnight causes a decrease in the average kinetic energy of the air molecules inside the tires, resulting in a decrease in tire pressure, which triggers the low tire pressure warning light.

Hope this helps!

a train has an initial velocity of 30 m/s. If the train accelerates uniformly at a rate of 6.3 m/s ^ for 2.8 seconds what is the trains final velocity?

Answers

T

Answer:

the velocity is a second final to initial velocity of 39

what is the velocity of the object 2.3 seconds after it is released from the top of the empire state building?

Answers

Explanation:

Object is under the effect of the acceleration of gravity

v = 1/2 a t^2       a = 9.81 m/s^2   t = 2.3

v = 25.9 m/s^2 = ~ 26 m/s   ( two significant digits)

Which expenses do you think will change based on how much you drive

Answers

Increased driving can lead to higher vehicle maintenance and repair expenses, increased fuel costs, potential increases in auto insurance premiums, and additional parking fees, all of which should be considered when estimating the overall impact on your expenses.

The expenses that are likely to change based on how much you drive can be broadly categorized into two main areas: vehicle-related expenses and fuel-related expenses.

1. Vehicle-related expenses: The more you drive, the more wear and tear your vehicle will experience, leading to increased maintenance and repair costs. Regular oil changes, tire replacements, brake pad replacements, and other routine maintenance tasks will be required more frequently.

2. Fuel-related expenses: It's intuitive that the more you drive, the more fuel you'll consume, resulting in higher fuel expenses. Fuel prices can vary, but regardless of fluctuations, increased mileage will directly impact your fuel budget. Fuel-efficient vehicles may mitigate some of these costs, but the overall impact on your expenses will still be noticeable.

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Consider the compound whose condensed structural formula is shown below: CH3CH2COCH2CH2CH3 This compound ______ O can be reduced to form 3-hexene O can undergo only oxidation and reduction reactions O is named as 3-hexanal O can be formed by the oxidation of 3-hexanol Your body monitors the nutrients it needs (our bodies know more than science...), and if a nutrient is low, our body tells us to eat. That's it - because for thousands of years, that's all we had to do was eat whole foods (or only slightly processed grains for bread, etc.). But now we have food that is devoid of nutrients due to processing - but our bodies don't know this - food is supposed to contain lots of nutrients. you have a score of x = 65 on an exam. which set of parameters would give you the best grade on the exam? Hunger in Asia-Pacific According to the 2021 Asia and the Pacific Regional Overview of Food Security and Nutrition, in this region alone, more than one billion people did not have access to adequate food in 2020 - an increase of almost 150 million people in just one year. The high cost of a healthy diet, and persistently high levels of poverty and income inequality, continue to hold healthy diets out of reach for 1.8 billion people in the Asia and Pacific region.3. Explain two economic consequences of the hunger crisis for the region and suggest one recommendation to overcome the problem. (500 max) A population of fruit flies grows exponentially. At the beginning of the experiment, the population size is 250. After 29 hours, the population size is 386. Find the doubling time for this population. When building a house, the number of days required to build varies inversely with the number of workers. One house was built in 20 days by 28 workers. How many days would it take to build a similar house with 14 workers? 1 Help Save & Exit 9 The conceptual framework summarizes the qualitative characteristics and supportive building blocks that are required to prepare financial information. How were the shamans and medicine men regarded in Indian societies?a) Native Americans in general viewed them with mistrust.b) Native American women, in particular, tended to reject them.C) Native Americans viewed them as highly paid witches.d) Native Americans regarded them as murderers.e) Native Americans in general treated them with respect. Identity the coterminal angle between 360 and 360 for the angle - 120No Part a:the diagram below shows a cross section of a cell membrane. Describe the basic structure of the cell membrane. Which of the following does not characterize federal transfer taxes?a) The tax is based on the value of property transferred by gift or at death.*b) The tax is a transaction tax.c) The tax is imposed on individuals but not on corporations.d) All of the above characterize federal transfer taxes. Select all the correct answers.The area of a baseball field bounded by home plate, first base, second base, and third base is a square. If a player at first base throws the ball to a player at third base, what is the distance the player has to throw?A. 16,200B. C. D. Oakwood Financial Inc. was organized on February 28. Projected selling and administrative expenses for each of the first three months of operations are as follows:March $132,700April 124,700May 113,500Depreciation, insurance, and property taxes represent $28,000 of the estimated monthly expenses. The annual insurance premium was paid on February 28, and property taxes for the year will be paid in June. 73% of the remainder of the expenses are expected to be paid in the month in which they are incurred, with the balance to be paid in the following month.Prepare a schedule indicating cash payments for selling and administrative expenses for March, April, and May. De qu material construyeron sus estructuras los Incas?a. de maderaC. de piedrab. de arenad. de barroPlease select the best answer from the choices provided Consider F and C below. F(x, y, z) = 2xz + y2 i + 2xy j + x2 + 15z2 k C: x = t2, y = t + 1, z = 3t 1, 0 t 1 (a) Find a function f such that F = f. f(x, y, z) = (b) Use part (a) to evaluate C f dr along the given curve C. History of the holocaust. Please help. What is the value of x in the equation 6 3 6 1 6 4 = 1 6 x ? You just received your syllabus and your list of supplies from your teacher. You are texting your mother at the store and telling her what she needs to buy. Complete the text with at least four school supplies. Sil te plat maman, je voudrais _________, __________, __________, _______. un stylo, un lve, un livre, un cahier une fentre, une craie, un livre, un prof une gomme, un cahier, un stylo, un livre une gomme, un crayon, un prof, beaucoup de papiers FREE POINTTTTTTTTTTTTTTTTTTT to be useful and meaningful in an economy, money must be _____.