/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 47 A trash compactor can compress i... [FREE SOLUTION] | 91Ó°ÊÓ

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A trash compactor can compress its contents to 0.350 times their original volume. Neglecting the mass of air expelled, by what factor is the density of the rubbish increased?

Short Answer

Expert verified
The density of the rubbish is increased by a factor of approximately \(2.857\) when compressed by the trash compactor.

Step by step solution

01

Write down the initial and final volume

The initial volume of the rubbish is V1, and the trash compactor can compress it to 0.350 times its original volume. So, the final volume V2 = 0.350 * V1.
02

Write the formula for density

The density formula is given by: density = mass/volume. Since we're neglecting the mass of the expelled air, we'll assume the mass of the rubbish remains constant during the process. Let's denote the initial density as D1 and the final density as D2.
03

Calculate the initial density

To calculate the initial density of the rubbish, we'll use the formula: D1 = mass/V1.
04

Calculate the final density

To calculate the final density of the rubbish, we need to use the compressed volume V2 from Step 1, which is 0.350 * V1. Using the density formula, D2 = mass/V2 = mass / (0.350 * V1).
05

Find the factor by which the density of the rubbish is increased

Now, we want to find how many times the final density D2 is greater than the initial density D1. To get this factor, we'll divide D2 by D1: Factor = (mass / (0.350 * V1)) / (mass / V1) Notice that the mass terms will cancel out.
06

Simplify and find the factor

To simplify the expression, we'll first invert the fraction in the denominator and multiply: Factor = (mass / (0.350 * V1)) * (V1 / mass) Now, cancel out the mass terms and V1 terms: Factor = 1 / 0.350 Finally, divide 1 by 0.350 to find the factor: Factor ≈ 2.857 The density of the rubbish is increased by a factor of approximately 2.857 when compressed by the trash compactor.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Volume Compression
Volume compression refers to the reduction of space that an object or substance occupies. In the context of our problem, we have a trash compactor that reduces the volume of rubbish to 0.350 of its original size. This means that what originally occupied a whole space now occupies just a little more than a third of that space.

When you compress volume, the amount of space decreases, but it's important to know that this change doesn't necessarily alter the mass of the substance involved, unless something is explicitly removed or added. In our case, any air inside the rubbish might be expelled, but we assume it doesn't change the mass of the solid waste itself significantly.
  • Initial Volume (V1) = original space occupied
  • Final Volume (V2) = compressed space after using the compactor = 0.350 * V1
Understanding volume compression helps us grasp how various systems operate under physical constraints, where space-saving and structural integrity are key.
Mass Conservation
Mass conservation is a fundamental principle in physics which states that mass in a closed system remains constant over time, regardless of the processes acting inside the system. In simple terms, mass cannot be created or destroyed within a closed environment.

In our example, when rubbish is compacted, the assumption is that the mass stays the same because we're only changing the space it takes up, not the actual amount of material. This principle allows us to simplify calculations by focusing solely on changes to volume and density rather than needing to track intricate changes to mass.
  • Mass before compression = Mass after compression
  • Allows us to focus on volume changes
This principle is crucial in many physics problems as it provides a basis for calculating other factors, such as density.
Density Increase
Density is a measure of how much mass is contained within a given volume. It is calculated using the formula: \( \text{Density} = \frac{\text{Mass}}{\text{Volume}} \).

In the problem at hand, by compressing the rubbish's volume while keeping the mass the same (mass conservation in action), we increase its density. Since the volume decreases to 0.350 of its original size without changing the mass, we see a direct increase in density: the mass is "packed" into a smaller space.
  • Initial Density (D1) = \( \frac{\text{Mass}}{V1} \)
  • Final Density (D2) = \( \frac{\text{Mass}}{0.350 \times V1} \)
  • Density Increase Factor = \( \frac{D2}{D1} = \frac{1}{0.350} \)
Understanding this relationship helps us see how materials can become more or less dense under compression, which has applications in packaging, materials science, and beyond.
Compact Rubbish
Compacting rubbish is a common practice that reduces waste volume. This practice achieves not only better use of space but often results in a more manageable mass for recycling or waste management.

By using a compactor, waste is reduced in volume, making disposal or recycling processes more efficient. Space savings often translate to lower transportation costs and reduced landfill use. Therefore, compacting is a critical aspect of modern waste management leading to sustainable practices.
  • Reduces volume, thereby saving space
  • Allows for more efficient waste management and recycling
  • Supports sustainability efforts
In essence, compacting rubbish helps us deal with waste in an eco-friendly manner by minimizing its impact on the environment.
Physics Problems
Physics problems often involve understanding how changes in one property affect others. In our trash compactor example, several concepts interlink to provide a clear understanding of how physics principles operate in real-world applications.

Problems like this push us to apply different principles in harmony - like using mass conservation to understand the changes in density due to volume compression. This ability to synthesize information is crucial to solving complex issues efficiently.
  • Demonstrates the connection between theory and practical application
  • Promotes critical thinking skills
  • Encourages students to explore how fundamental physics concepts like mass and volume interact
Solving physics problems by applying these principles helps build a deeper understanding of how our world operates, encouraging students to not only learn theories but also their implications in reality.

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