In which of the following is positive work done by a person on a suitcase

Answers

Answer 1

The work done by man is positive as long as force applied by man on the suitcase and the displacement of suitcase are parallel. Since no other force is acting on suitcase other than gravitational force by Earth and force applied by man, ignoring force applied by moon and sun since they are negligible, if he holds suitcase still, then work done by him will be zero. If he lifts suitcase in upward direction, work done by him will be positive but work done by gravity will be negative since gravity acts towards the centre of the Earth and displacement of suitcase is opposite to that force.
Option 3 is interesting, if you are sitting on a chair(which is at rest) and analyzing the man holding the suitcase who is standing on moving walkaway, work done by man on case will be zero because displacement of case is in horizontal direction but force applied by man is upward. i.e, force and displacement are both perpendicular.

Hence option 2 is correct.

Answer 2

Final answer:

Positive work is done when a person moves a suitcase in the direction of the applied force, such as carrying it up stairs. No work is done when holding a suitcase stationary or moving it horizontally without vertical displacement. Friction can affect the net work done on an object by doing negative work.

Explanation:

In scenarios where positive work is done by a person on a suitcase or briefcase, energy is being transferred to the object due to a force having a component in the direction of the object's motion. For example, carrying a briefcase up stairs at a constant speed involves positive work because the force applied by the person has a component in the direction of motion, effectively transferring energy to the briefcase. On the other hand, when a person holds a briefcase without moving it, or moves it horizontally at a constant speed with no vertical displacement, no work is done since there is no displacement in the direction of the applied force, thus no energy transfer occurs.

Furthermore, when discussing net work, it is important to consider all forces acting on the object, including friction. While a person may do a certain amount of work on an object, if friction is present it does negative work, which counters some of the energy put into the system by the person, resulting in a different value for net work.

Related Questions

Which of the following best illustrates a pair of sentences that are joined by an understood relationship?

A. Luke put three dollars into the office football pool. He was looking forward to vacation.

B. Detective Smiley scanned the dim hallway. He pulled his pistol from its holster.

C. It rained for ten days and ten nights. Grandmother Grady called a company to drill a well.

D. I don't understand a word you said. Have you taken a course in English literature?

Answers

B. Detective Smiley scanned the dim hallway. He pulled his pistol from its holster. Because is you're a cop and you're in the dark, you're gonna take out your gun

I WILL GIVE BRAINLIEST 50!!!!!

What is convection?

Transfer of heat through objects touching source
Transfer of heat through direct physical contact
Transfer of heat through electromagnetic waves
Transfer of heat through the movement of particles

Answers

Convection is the movement of denser (cooler) materials falling and less dense (hotter) materials rising. This creates a cycle because the materials usually then heat up or cool, which restarts the movement again. Therefore, convection would be the transfer of heat through the movement of particles.

What is a tectonic plate? a section of the earth's crust that is moving in response to the motion of the mantle beneath. a mountain range on earth a section of the venus's crust that is moving in response to the motion of the mantle beneath. an earthquake?

Answers

A mountain range on earth is your answer :)

What advantages do sports drinks or juices have over water in terms of electrolyte content? Why does this matter for strenuous exercise?

Answers

Sports drinks do offer some benefits when comparing sports drinks vs. water. While water actually works better at fluid replacement, sports drinks are often more appealing to the palate. In other words, people who enjoy the taste of sports drinks may drink more of a sports drink than they would water; this will lead to better hydration.

Sports drinks also contain electrolytes and carbohydrates. While exercising for short periods of time, it is not necessary to replace electrolytes; however, athletes and marathon participants exercising for period of an hour or more can benefit from electrolyte replacement in particular. Carbohydrates offer the body energy. When the body burns calories, it needs carbohydrates to replace energy lost. The longer the workout, the more carbohydrates are needed.

Final answer:

Sports drinks or juices have advantages over water in terms of electrolyte content, as they provide a source of electrolytes that help replenish those lost during strenuous exercise. Electrolytes are minerals that maintain fluid balance and support muscle and nerve function.

Explanation:

In terms of electrolyte content, sports drinks or juices have advantages over water. Electrolytes are minerals that help maintain the balance of fluids in the body and aid in nerve and muscle function. During strenuous exercise, the body loses electrolytes through sweat. Sports drinks or juices contain electrolytes such as sodium, potassium, and magnesium, which help replenish the lost electrolytes and maintain hydration.

Water, on the other hand, does not contain electrolytes. While it is essential for hydration, it does not provide the same replenishment of electrolytes as sports drinks or juices. This is particularly important during strenuous exercise as the loss of electrolytes can lead to muscle cramps, fatigue, and impaired performance.

In conclusion, sports drinks or juices have an advantage over water in terms of electrolyte content because they provide a source of electrolytes that help replenish those lost during strenuous exercise, supporting hydration and maintaining optimal muscle and nerve function.

Learn more about Electrolyte content in sports drinks and water here:

https://brainly.com/question/32661168

#SPJ6

For most people, getting 8 to 9 hours of sleep increases concentration, improves physical health, and improves one's mood.

Please select the best answer from the choices provided.

T
F

Answers

That statement is true

Answer: The given statement is true.

Explanation:

It is known that when we get enough sleep then we feel refreshed. Also, sleeping for 8 to 9 hours helps in the improvement of health of a person because more we sleep more our mind remains relaxed.

As a result, we feel good, happy and delighted. Therefore, we are able to focus on our goals with more concentration.

Thus, we can conclude that the statement for most people, getting 8 to 9 hours of sleep increases concentration, improves physical health, and improves one's mood, is true.

While conducting a lab experiment, Ali calculated that 1.20 E6 Joules of heat were needed to melt of 18.5 kilograms of an unknown substance at its melting point. What is the latent heat of fusion of the substance?

Answers

1.20 E^6/18.5=6.48E^4

Final answer:

The latent heat of fusion is the heat required to change a substance from solid to liquid state. In this case, the latent heat of fusion is calculated for an unknown substance when 1.20 E6 Joules of heat melts 18.5 kilograms of it.

Explanation:

The latent heat of fusion of a substance is the amount of heat required to change one mole of a substance from the solid to the liquid state.

In this case, we can calculate the latent heat of fusion by using the formula Q = m * Lf, where Q is the heat required, m is the mass of the substance, and Lf is the latent heat of fusion.

For the given scenario with 18.5 kg of the unknown substance and 1.20 E6 Joules of heat needed, we can calculate the latent heat of fusion as:

Convert 1.20 E6 J to kJ: 1.20 E6 J = 1200 kJ

Calculate Lf: Lf = Q / m = 1200 kJ / 18.5 kg

Lf = 64.86 kJ/kg

What minimum speed must the rocket have just before impact in order to save the explorer's life?

Answers

Answer: Assuming that I understand the geometry correctly, the combine package-rocket will move off the cliff with only a horizontal velocity component. The package will then fall under gravity traversing the height of the cliff (h) in a time T given by h = 0.5*g*T^2 However, the speed of the package-rocket system must be sufficient to cross the river in that time v2 = L/T Conservation of momentum says that m1*v1 = (m1 + m2)*v2 where m1 is the mass of the rocket, v1 is the speed of the rocket, m2 is the mass of the package, and v2 is the speed of the package-rocket system. Expressing v2 in terms of v1 v2 = m1*v1/(m1 + m2) and then expressing the time in terms of v1 T = (m1 + m2)*L/(m1*v1) substituting T in the first expression h = 0.5*g*(m1 + m2)^2*L^2/(m1*v1)^2 solving for v1, the speed before impact is given by v1 = sqrt(0.5*g/h)*(m1 + m2)*L/m1

How fast is the sixth cosmic velocity?

Answers

25,000 miles per hour

hope that this helps

Other Questions

jamal was born 34 weeks after he was conceived and weighed 6 pounds. jamal is best described as Smita wants to find new ways to recycle materials. Which field of study would be most useful to her? A. MeteorologyB. ChemistryC. MicrobiologyD. Zoology I do not understand any of this On the surface cost benefit analysis seems straightforward Why did the people in the region rejoice when the Assyrian Empire was defeated? What is one possible effect of global warming? The oceans may evaporate and continents could become larger. Areas that support agriculture could become deserts. Lower temperatures could result in lower population levels. The earths deserts may disappear. Congressional committees both aid and _____ the legislative process. Select the four reasons why Eastern luxuries were expensive.production difficultiesdistance they had to be broughttaxes en routefrequent loading and unloadingdiscounts to large carriersdanger from pirates and robbershigh wages for workers The angles of a quadrilateral are 140, 80, 60, and 80What type of quadrilateral could it be? The challenge for today's artists is "What new is there to say?" TrueFalse Match each scenario with the step in the home-buying process it describes What are the tense and voice of the italicized verb in the following sentence? Before he enters the race, he will have been examined by his doctor. future perfect passive future passive present perfect passive future perfect active Parks spent 1/3 of his money on a sweater. He spent 3/5 of the remainder on a pair of jeans. If he has $36 left, how much did the sweater cost? to meet cellular needs for food,water,energy,waste removal,multicellular organisms have developed various specializations,such as organs,and organ systems. if the waste you have contains 100.0 grams of silver nitrate, how many mols of silver nitrate is this what is the role of b cells in the human immune system What right does the Second Amendment guarantee, and what is one point of disagreement people have about this right? Describe how the Supreme Court has interpreted this right in a major court case 1. Which element of plot matches the definition?the outcome of the conflict in a plot(1 point)resolutionexpositionrising actionfalling action The term feudal comes from the latin feudum, which refers to: Cierto o falso? According to Venezuelan customs, you shouldn't eat until your hostess tells you buen provecho. Steam Workshop Downloader