Three Ways To Levitate A Magic Carpet Reading Answer

IELTS Academic Reading Passage
20:00

It sounds like a science fiction joke, but it isn’t. What do you get when you turn an invisibility cloak on its side? A mini flying carpet. So say physicists who believe the same exotic materials used to make cloaking devices could also be used to levitate tiny objects. In a further breakthrough, two other research groups have come a step closer to cracking the mysteries of levitation.

Scientists have levitated objects before, most famously using powerful magnetic fields to levitate a frog. But that technique, using the repulsive force of a giant magnet, requires large amounts of energy. In contrast, the latest theories exploit the natural smaller amounts of energy produced by the quantum fluctuations of empty space.

In May 2006, two research teams led by Ulf Leonhardt at St Andrew’s University, UK, and John Pendry at Imperial College, London, independently proposed that an invisibility cloak could be created from exotic materials with abnormal optical properties. Such a cloaking device – working in the microwave region – was manufactured later that year.

The device was formed from so-called ‘meta materia Is’ exotic materials made from complex arrays of metal units and wires. The metal units are smaller than the wavelength of light and so the materials can be engineered to precisely control how electromagnetic light waves travel around them. They can transform space, tricking electromagnetic waves into moving along directions they otherwise wouldn’t,’says Leonhardt.

Leonhardt and his colleague Thomas Philbin, also at St Andrew’s University, realised that this property could also be exploited to levitate extremely small objects. They propose inserting a metamaterial between two so-called Casimir plates. When two such plates are brought very close together, the vacuum between them becomes filled with quantum fluctuations of the electromagnetic field. As two plates are brought closer together, fewer fluctuations can occur within the gap between them, but on the outer sides of the plates, the fluctuations are unconstrained. This causes a pressure difference on either side of the plates, forcing the plates to stick together, in a phenomenon called the Casimir effect.

Leonhardt and Philbin believe that inserting a section of metamaterial between the plates will disrupt the quantum fluctuations of the electromagnetic field. In particular, metamaterials have a negative refractive index, so that electromagnetic light waves entering a metamaterial bend in the opposite way than expected, says Leonhardt.That will cause the Casimir force to act in the opposite direction – forcing the upper plate to levitate. The work will appear in the New Journal of Physics.

Federico Capasso, an expert on the Casimir effect at Harvard University in Boston, is impressed.’Using metamaterials to reverse the Casimir effect is a very clever idea,’ he says.

However, he points out that because metamaterials are difficult to engineer, it’s unlikely that they could be used to levitate objects in the near future.

But there are good signs that quantum levitation could be achieved much sooner, by other methods. Umar Mohideen at the University of California Riverside and his colleagues have successfully manipulated the strength of the Casimir force by increasing the reflectivity of one of the plates, so that it reflects virtual particles more efficiently. Modifying the strength of the Casimir force is the first step towards reversing it, says team member Galina Klimchitskaya at North-West Technical University in St Petersburg, Russia.

Capasso and his colleagues have also been working on an alternative scheme to harness a repulsive Casimir effect Their calculations show that a repulsive Casimir force could be set up between a 42.7 micrometre-wide gold-coated polystyrene sphere and a silicon dioxide plate, if the two are immersed in ethanol. ‘Although the Casimir force between any two substances – the ethanol and gold, the gold and the silicon dioxide, or the silicon dioxide and the ethanol – is positive, the relative strengths of attraction are different, and when you combine the materials, you should see the gold sphere levitate,’ he says.

Capasso’s early experiments suggest that such repulsion could occur, and that in turn could be used to levitate one object above another.’It’s very early work, and we still need to make certain this is really happening, but we are slowly building up experimental evidence for quantum levitation,’says Capasso, who presented his results at a conference on Coherence and Quantum Optics in Rochester, New York, in June.

This is a very exciting experimental result because it is the first demonstration that we can engineer a repulsive Casimir force,’ says Leonhardt.

Questions 1-5

Do the following statements agree with the claims of the writer in Reading Passage 3? Write

YESif the statement agrees with the writers claims

NO if the statement contradicts the writers claims

NOT GIVEN if it is impossible to say what the writer thinks about this

  1. A mini flying carpet is a possibility according to some scientists.
  2. Cloaking devices can be used for levitation.
  3. Scientists now know all about levitation.
  4. Things can be transported from place to place using empty space technology.
  5. The most recent research into levitation has made use of large magnets.

Questions 6-10

Choose the correct letter, A, B, C or D.

6. Ulf Leonhardt and John Pendry

A worked together on a project in 2006.

B both came up with the same idea.

C invented the microwave oven.

D used only basic objects in their research.

7. Metamaterials are

A similar to light, but with a smaller wavelength.

B a combination of simple metals and wires.

C able to change where electromagnetic waves go.

D engineered when light waves travel around them.

8. The importance of the Casimir effect is that it

A doesn’t require a vacuum in order to work.

B increases the number of plates that can be used.

C creates large and frequent fluctuations.

D creates pressure difference and stickiness.

 

9. Leonhardt and Philbin think that putting a metamaterial between two plates will

A cause the top plate to rise above the bottom plate.

B stop electromagnetic light waves bending.

C stop the Casimir force from working.

D not affect electromagnetic fluctuations.

10. Why is it important to change the strength of the Casimir force?

A to reflect the plates

B to help reverse the force

C to see virtual particles better

D to enable other scientists to progress

Questions 11-13

Complete each sentence with the correct ending A-F below.

  1. Capasso is unconvinced that
  2. Capasso has calculated that
  3. Capasso has admitted that

A gold can be used to produce levitation.

B a particular type of ethanol has to be used.

C the levitation will last for only a few seconds.

D using metamaterials will help lead to levitation in the short term.

E his experiment will be extremely costly to perform.

F his idea is still only a theory.

IELTSVisa Logo

Solution For: Three Ways To Levitate A Magic Carpet Reading Answer

1. YES 8. D
2. NO 9. A
3. NO 10. B
4. NOT GIVEN 11. D
5. NO 12. A
6. B 13. F
7. C

R

Review and Practice

  • Regularly practice with IELTS reading samples and time yourself to get used to the pressure of the exam.
  • Review your mistakes to understand where you went wrong and how to avoid similar errors in the future.

Our Books

Master IELTS Speaking Part 1

IELTS Writing Task 1 Book

IELTS Writing Task 2 Book

Three Ways To Levitate A Magic Carpet Reading Answer Explanation

Comin Soon

Practice IELTS Other Modules

IELTS Listening

The IELTS Listening test assesses how well you can understand spoken English in various contexts. It lasts about 30 minutes and is divided into four sections with a total of 40 questions. The listening tasks become increasingly difficult as the test progresses.

IELTS Academic Reading

The IELTS Academic Reading section assesses your ability to understand and interpret a variety of texts in academic settings. It is designed to evaluate a range of reading skills, including skimming for gist, reading for main ideas, reading for detail, understanding inferences, and recognizing a writer's opinions and arguments.

IELTS Speaking

The IELTS Speaking test assesses your ability to communicate in English on everyday topics. It lasts 11-14 minutes and consists of three parts: introduction, cue card, and a discussion based on the cue card topic.

IELTS General Reading

IELTS General Reading tests your ability to understand and interpret various types of texts. Here are some key areas and types of content you can expect to encounter in the reading section, along with tips for effective preparation.

IELTS Academic Writing Task 1

In IELTS Academic Writing Task 1, you are presented with a visual representation of information, such as graphs, charts, tables, or diagrams, and you are required to summarize, compare, or explain the data in your own words.

IELTS General Writing Task 1

In IELTS General Writing Task 1, you are required to write a letter based on a given situation. The letter can be formal, semi-formal, or informal, depending on the prompt. Here’s a breakdown of the key components to include in your letter

IELTS Academic Writing Task 2

In IELTS Academic Writing Task 2, you are required to write an essay in response to a question or topic. Here’s a guide to help you understand the essential elements of this task

IELTS Exam Tips

To succeed in the IELTS exam, practice regularly, familiarize yourself with the test format, improve your vocabulary, develop time management skills, and take mock tests to build confidence.

Grammer for IELTS

Grammar is the foundation of effective communication in English. Understanding tense usage, subject-verb agreement, and sentence structure enhances clarity and coherence in writing and speaking.

Vocabulary for IELTS

Vocabulary plays a crucial role in the IELTS (International English Language Testing System) exam, especially in the Speaking and Writing sections. Here’s an overview of why vocabulary is important and how it impacts your performance

RECENT IELTS SAMPLES QUESTIONS AND ANSWERS

Our IT Company Services

Pin It on Pinterest

Share This