# Efficiency of Objects Pushed Up a Ramp

• Emperor
In summary: Keep practicing and you'll get the hang of it! Remember to carefully read the question and make sure you understand what is being asked. And don't be afraid to ask for help if you get stuck. Good luck!In summary, the objects A, B, and C with masses of 2.0 kg, 1.0 kg, and 1.0 kg, respectively, are being pushed up a 4.0 m ramp with a height of 1.2 m. The applied forces are parallel to the ramp and have magnitudes of 9.8 N on A, 4.9 N on B, and 3.1 N on C. To calculate efficiency, the formula W(output) ÷
Emperor

## Homework Statement

Objects A (2.0 kg), B (1.0 kg), and C (1.0 kg) are pushed up a ramp, which is 4.0 m and 1.2 m high. The applied forces are parallel to the ramp with magnitudes of 9.8 N on A, 4.9 N on B, and 3.1 N on C.

## Homework Equations

Eff = W(output) ÷ E(Input) x 100%

W = F x d

E(potential) = mgh

## The Attempt at a Solution

Efficiency of A:

W(output) = 9.8 N x (4 + 1.2) = 50.96 J

E(potential) = 2 x 9.8 x (4 + 1.2) = 101.92 J

Eff = 50.96 ÷ 101.92 x 100 = 20% Efficiency

I know I'm probably over-thinking this one tiny equation but the thing is, I've spent 1 and a half hours on this question alone. The answers I'm supposed to get are "A: 60%, B: 60%, C: 95%" but I can't get anywhere close to them no matter what I do. Maybe its because I forgot how to add the ramp components together, but I thought that was correct. I resorted to guessing as well, but literally no combination of numbers can get me to that answer; its inconceivable for me. I also have a formula sheet on me as well, but I don't know which one to use. This is also literally the only question on my review sheet that I cannot understand at all... Like I said, I think I'm definitely over-thinking it. May someone enlighten me on my mistakes?

What do you think the 4m distance is measuring? Why are you adding it to the 1.2m?
The question is not very clear... do you think the objects are accelerating up the ramp? If not, what do you think all the forces are on the objects as they move?

Your post is not clear on the dimensions of the ramp. Is the ramp supposed to be 4.0 m long measured horizontally or along the sloping surface?

Emperor said:
Efficiency of A:

W(output) = 9.8 N x (4 + 1.2) = 50.96 J

What you said is "work output" would actually be "work input" and the potential energy gained would be the "work output"

Also, the object is pushed up the ramp, and the force is parallel to the ramp. The displacement is only 4 meters (you wouldn't add the 1.2 like you did). Input work would just be 9.8*4=39.2 J

Emperor said:
E(potential) = 2 x 9.8 x (4 + 1.2) = 101.92 Joules

The change in potential energy is mgh. It would be 2*9.8*1.2=23.52 Joules (you don't add the the 4 meters, only the change in height matters)So you would get:

Efficiency = 23.52 / 39.2 = 0.6 = 60%
Try doing the other problems now and post if something went wrong.

The 4m is going up the ramp, while the height is 1.2 m. Its hard to describe because I can't draw the picture here.

Edit: Thanks Nathaneal for the quick response, and it was correct! You saved me, thank you very much.

Last edited:
Emperor said:
You saved me, thank you very much.

No problem :)

## What is the "Annoying Efficiency Problem"?

The "Annoying Efficiency Problem" refers to a common issue in scientific research where certain factors or variables can greatly affect the efficiency or accuracy of experiments or data analysis.

## What causes the "Annoying Efficiency Problem"?

There are many potential causes for the "Annoying Efficiency Problem," including human error, faulty equipment, inconsistent data, or inadequate sample sizes. It can also be caused by external factors such as time constraints or budget limitations.

## How does the "Annoying Efficiency Problem" impact scientific research?

The "Annoying Efficiency Problem" can greatly impact the reliability and validity of scientific research. It can lead to inaccurate or inconclusive results, which can hinder the progress of a particular field of study or delay the development of new technologies or treatments.

## What can scientists do to address the "Annoying Efficiency Problem"?

To address the "Annoying Efficiency Problem," scientists can take measures to minimize potential sources of error, such as using standardized protocols and controls, increasing sample sizes, and regularly calibrating equipment. They can also collaborate with other researchers to validate their findings and replicate experiments.

## How can the "Annoying Efficiency Problem" be prevented?

While it may not be entirely preventable, the "Annoying Efficiency Problem" can be minimized by implementing rigorous quality control measures and continuously monitoring and adjusting experimental procedures. Regularly reviewing and updating research protocols can also help prevent potential efficiency problems.

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