Can anyone let me know and define about fermi questions / problems and give me some intersting questions and solutions related to it. Regards cgnanij
From India, Madras
9From India, Madras
Fermi problems are the puzzles and riddles asked in the interviewers in the MNCs nowadays. For example "What is the weight of earth?" answer could be " since it rotates in the universe freely, so it is weightless". For more have al look on Times Accent dated 3 Dec 2008.
From India, Delhi
From India, Delhi
Fermi Problems are the set of problems or situations which showcases various capability strengths of individual answering these problems. It involves making logical assumptions to certain hypothetical situations with restricted information in hand. For e.g - How many golf balls are there in india?? It doesn't only check the decision making and analytical ability of an individual but also focuses more on a process oriented approach of an individual.
Thanks
Jitender
Consultant - Cerebrus Consultant
From India, Mumbai
Thanks
Jitender
Consultant - Cerebrus Consultant
From India, Mumbai
Fermi question's goal is to get an answer to an order of magnitude (typically a power of ten) by making reasonable assumptions about the situation, not necessarily relying upon definite knowledge for an "exact" answer.
A Fermi question demands communication.
A Fermi question utilizes estimation.
A Fermi question emphasizes process rather than "the" answer.
It is developed by ENRICO FERMI (was an Italian physict)
Thanks & Regards,
Nawaz
From Kuwait, Kuwait
A Fermi question demands communication.
A Fermi question utilizes estimation.
A Fermi question emphasizes process rather than "the" answer.
It is developed by ENRICO FERMI (was an Italian physict)
Thanks & Regards,
Nawaz
From Kuwait, Kuwait
Fermi was a NL (nobel Laurete) in Physics and did path breaking research in fission which lead to the discovery of A bomb.He used to challenge his students in U of Chicago with "Fermi" questions which necessitates making logical assumptions to hypothetical problems.
You can actually googlethis.Microsoft has been using this kind of questions in their interview techniques to assess the capacity of students to think on their feet. Mainly used to understand the approach of the candidates to use their alertness and ability to think on their feet. Try searching under "Fermi questions" by microsoft.
best wishes
From India, Pune
You can actually googlethis.Microsoft has been using this kind of questions in their interview techniques to assess the capacity of students to think on their feet. Mainly used to understand the approach of the candidates to use their alertness and ability to think on their feet. Try searching under "Fermi questions" by microsoft.
best wishes
From India, Pune
Here is the book "How would you move Mount Fuji".You will get many questions in last two chapters. Regards,
Hello All..
Here are some questions that I found on the net...u might find these interesting
Fermi Problems: Solve Them If You Dare...
1. How many frames are in a Walt Disney animated movie such as Tarzan?
2. What is the mass of a fully loaded cement truck?
3. What is the mass of a fully loaded Boeing 747?
4. If you were to stack a pile of one dollar bills corresponding to the US national debt,
A. how high would it reach?
B. how much would it weigh?
C. what would be the pressure on the bottom dollar?
5. What is the length in miles of the US Interstate Highway system?
6. How many molecules come off a car tire with each revolution?
7. How many gallons of water move down the Mississippi River in one day?
8. How many piano tuners would you expect to find in the local telephone directory?
9. How much energy is released due to latent heat of vaporization when a hurricane dumps 16 inches
of rain on North Carolina?
10. If a high explosive (e.g. TNT) releases as much energy per kilogram as food, how many people would the
energy of a 1-MT H-bomb feed for one day, if its energy could be converted to food at 100% efficiency?
11. How many square kilometers of surface would it take to supply the U.S. with all its energy needs if solar
energy could be converted with 1% efficiency? Allow for night time, cloud cover, etc. The solar constant
is 1.35 kW/m2.
12. If all the oxygen atoms breathed by Enrico Fermi over his lifetime are now distributed uniformly through the
atmosphere, how many of these atoms do you breathe in with each breath?
13. If you could get a penny for each time someone said "Ouch!" in the United States, how long would it take you to become a billionaire?
14. If all the ball-bearings in all the fishing reels in the U.S. were dumped into a single grain elevator silo, how tall
would the silo have to be?
15. If we used ALL the electrical energy in the world to operate motor that could slow down the earth with 1% efficiency,
how many days (as measured by Earth rotations) would it take to bring the rotation of the Earth to a halt?
16. Pick a nearby tree. Estimate the number of leaves on the tree.
17. Assuming that energy is transferred with 100% efficiency, how much soup could be heated up from room temperature to "hot soup eating temperature" by making use of all of the energy expended in playing a game of pool? Note: This problem was devised a few meters from the pool tables at the Reynolds Club at the University of Chicago, which is not far from the old squash courts. If you don't know the significance of the U of C squash courts to physics, look it up!
From United Kingdom, London
Here are some questions that I found on the net...u might find these interesting
Fermi Problems: Solve Them If You Dare...
1. How many frames are in a Walt Disney animated movie such as Tarzan?
2. What is the mass of a fully loaded cement truck?
3. What is the mass of a fully loaded Boeing 747?
4. If you were to stack a pile of one dollar bills corresponding to the US national debt,
A. how high would it reach?
B. how much would it weigh?
C. what would be the pressure on the bottom dollar?
5. What is the length in miles of the US Interstate Highway system?
6. How many molecules come off a car tire with each revolution?
7. How many gallons of water move down the Mississippi River in one day?
8. How many piano tuners would you expect to find in the local telephone directory?
9. How much energy is released due to latent heat of vaporization when a hurricane dumps 16 inches
of rain on North Carolina?
10. If a high explosive (e.g. TNT) releases as much energy per kilogram as food, how many people would the
energy of a 1-MT H-bomb feed for one day, if its energy could be converted to food at 100% efficiency?
11. How many square kilometers of surface would it take to supply the U.S. with all its energy needs if solar
energy could be converted with 1% efficiency? Allow for night time, cloud cover, etc. The solar constant
is 1.35 kW/m2.
12. If all the oxygen atoms breathed by Enrico Fermi over his lifetime are now distributed uniformly through the
atmosphere, how many of these atoms do you breathe in with each breath?
13. If you could get a penny for each time someone said "Ouch!" in the United States, how long would it take you to become a billionaire?
14. If all the ball-bearings in all the fishing reels in the U.S. were dumped into a single grain elevator silo, how tall
would the silo have to be?
15. If we used ALL the electrical energy in the world to operate motor that could slow down the earth with 1% efficiency,
how many days (as measured by Earth rotations) would it take to bring the rotation of the Earth to a halt?
16. Pick a nearby tree. Estimate the number of leaves on the tree.
17. Assuming that energy is transferred with 100% efficiency, how much soup could be heated up from room temperature to "hot soup eating temperature" by making use of all of the energy expended in playing a game of pool? Note: This problem was devised a few meters from the pool tables at the Reynolds Club at the University of Chicago, which is not far from the old squash courts. If you don't know the significance of the U of C squash courts to physics, look it up!
From United Kingdom, London
In physics, particularly in physics education, a Fermi problem, Fermi question, or Fermi estimate is an estimation problem designed to teach dimensional analysis, approximation, and the importance of clearly identifying one's assumptions. Named for 20th century physicist Enrico Fermi, such problems typically involve making justified guesses about quantities that seem impossible to compute given limited available information.
Fermi was known for his ability to make good approximate calculations with little or no actual data, hence the name. One well-documented example is his estimate of the strength of the atomic bomb detonated at the Trinity test, based on the distance traveled by pieces of paper dropped from his hand during the blast.[1]
From India, Madras
Fermi was known for his ability to make good approximate calculations with little or no actual data, hence the name. One well-documented example is his estimate of the strength of the atomic bomb detonated at the Trinity test, based on the distance traveled by pieces of paper dropped from his hand during the blast.[1]
From India, Madras
General
From India, Madras
- Estimate the total number of hairs on your head.
- Estimate the number of square inches of pizza consumed by all the students at the University of Maryland during one semester.
- When it rains, water would accumulate on the roofs of flat-topped buildings if there were no drains. A heavy rain may deposit water to a depth of an inch or more. Given that water has a mass of about 1 gm/cm 3 , estimate the total force the roof of the physics lecture hall would have to support if we had an inch of rain and the roof drains were plugged.
- One suggestion for putting satellites into orbit cheaply without using rockets is to build a tower 300 km high containing an elevator. One would put the payload in the elevator, lift it to the top, and just step out into orbit. Ignoring other problems (such as structural strain on the tower), estimate the weight of such a tower if its base were the size of Washington DC and it were made of steel. (Steel is about 5 times as dense as water, which has a density of 1 gm/cm 3 .)
- Estimate the total amount of time 19 year olds in the US spent during this past semester studying for exams in college. (Not counting finals.)
- The deficit in the Federal Budget this past year was approximately $100 Billion ($10 11 ). (a)Assuming this was divided equally to every man, woman, and child in the country, what is your share of the debt?
(b) Supposing the deficit were paid in $1 bills and they were layed out on the ground without overlapping. Estimate what fraction of the District of Columbia could be covered.
(c) Suppose you put these $1 bills in packages of 100 each and gave them away at the rate of 1 package every 10 seconds. If you start now, when will you be finished giving them away?
(d) Are any of these calculations relevant for a discussion which is trying to understand whether the deficit is ridiculously large or appropriate in scale? Explain your reasoning. - The Federal Budget Deficit is approximately $100 Billion this year. Compare this to what we spend on what we eat by estimating the total amount US consumers spend on food in grocery stores, markets, and restaurants in one year.
- In the 1989 Loma Prieta earthquake in California, approximately 2 million books fell off the shelves at the Stanford University library. If you were the library administrator and wanted to hire enough part-time student labor to put the books back on the shelves in order in 2 weeks, how many students would you have to hire? (You may assume that the books just fell off the shelves and got a bit mixed up but books in different aisles did NOT get shuffled together.)
- Estimate the total number of sheets of 8.5 x 11 inch paper used by all the students at the University of Maryland in one semester.
- If the land area of the earth were divided up equally for each person on the planet, about how much would you get?
- After the gulf war, large areas of desert had to be cleared of mines using special bulldozers that simply sweep the sand in front of them like a snowplow, but whose blades are strong enough to withstand the explosion of a mine. Estimate how long it would take a single bulldozer to clear a patch of desert that is 10 km square.
- This winter, the East coast has been hit by a number of snow storms. Estimate the amount of work a person does shoveling the walk after a snow storm. Among your estimates you may take the following:
- The length of a typical path from a house to the street is 10 meters.
- Assume the snow fell to a depth of 4 inches.
- Assume the snow was only moderately packed so that its density was equal to 0.2 g/cm 3 -- about one fifth that of water.
- A floppy disk for a computer stores information by magnetizing small regions of the disk. For a typical floppy disk, estimate the area of the disk that corresponds to a single bit of information. (Remember: the storage capacity of a disk is cited in bytes where 1 byte = 8 bits.)
- Ali El-Ectrical is an Engineering student at your university taking a "normal" load (for Engineers!) and paying full tuition. Estimate how much he is paying for each hour of class time he spends with an instructor over one semester.
- Estimate the number of blades of grass a typical suburban house's lawn has in the summer.
- How many notes are played on a given radio station in a given year?
- How many pencils would it take to draw a straight line along the entire Prime Meridian of the earth?
- If all the string was removed from all of the tennis rackets in the US and layed out end-to-end, how many round trips from Detroit to Orlando could be made with the string?
- How many drops of waters are there in all of the Great Lakes.
- How many piano tuners are there in New York?
- How many atoms are there in the jurisdiction of the continental US?
- How far can a crow fly without stopping?
- How many golf balls can be fit in a typical suitcase?
- How tall is this building?
- Estimate the number of cars and planes entering the state at any given time.
- How much air (mass) is there in the room you are in?
- How long does it take a light bulb to turn off?
- ow much energy does it take to split a 2x4?
- How much milk is produced in the US each year?
- If you drop a pumpkin from the top of a ten story building what is the farthest a single pumpkin seed can land from the point of impact?
- How many flat tires are there in the US at any 1 time?
- Estimate the angular momentum that your body has as a result of the earth's turning on its axis.
- The mass of the earth is about 6x10 24 kg. Estimate the kinetic energy it has as a result of its orbiting the sun.
- A professor of physics is going ice skating for the first time. He has gotten himself into the middle of an ice rink and cannot figure out how to make the skates work. Every motion he makes simply slips on the ice and leaves him in the same place he started. He decides that he can get off the ice by throwing his gloves in the opposite direction.
(a) Suppose he has a mass M and his gloves have a mass m. If he throws them as hard as he can away from him, and they leave his hand with a velocity v. Explain whether or not he will move. If he does move, calculate his velocity, V.
(b) Discuss his motion from the point of view of the forces acting on him.
(c) If the ice rink is 10 m in diameter and the skater starts in the center, estimate how long it will take him to reach the edge, assuming there is no friction at all. - The orbiting Hubble telescope was recently repaired by a crew of astronauts from the Space Shuttle Endeavor. The Hubble is in a circular orbit 600 km above the surface of the earth. For half of the Hubble's orbital period it is in sunlight and for half it is in the darkness of the earth's shadow. As a results of the change in fit of the various parts of the Hubble due to heating and cooling of the telescope, the astronauts could only work on certain repairs while the Hubble was in darkness. Estimate how much time the astronauts had to work on these repairs before having to stop "for a sun-break".
- According to Newton's law of universal gravitation, the earth's gravity gets weaker as we go further from the earth. But when we drop a ball near the top of the lecture hall it doesn't seem to fall any differently than we drop it near the floor. Let g t stand for the gravitational acceleration observed at the top of the lecture hall and g b for it at the bottom. Estimate how much Newton's universal gravitation theory predicts g t will be less than g b . (Hint: It's easier if you estimate the fractional change, g b /g t - 1.)
- Suppose the Army Corps of Engineers decided to put a dam across the Potomac River in order to provide power for the Washington area. Assume the dam was built to hold back the water into a lake to a height of 15 m behind the dam. (Ignore the fact that this lake would cover land occupied by houses and cities.) Estimate the total force the water would exert on the dam. (Hint: If you have never seen the Potomac and have no idea as to how wide it is across, make a reasonable guess.)
- A ballistic rocket is shot straight up from Cape Canaveral. Its rockets fire briefly. After the firing, it has it a velocity of 8 km/sec and a mass of m. How far up will it go before it begins to fall back to earth? Calculate your answer to within 10%. Ignore the distance it travels while its rockets are firing, the resistance of the atmosphere, and the rotation of the earth. (Hint: If you don't remember the radius of the earth you can solve for d/R e where d is the distance it reaches measured from the center of the earth and R e is the radius of the earth.)
- For next year's Physics Open House the Department is planning to set up a bungee jump from the top of the physics building. Assume that one end of an elastic band will be firmly attached to the top of the building and the other to the waist of a courageous participant. The participant will step off the edge of the building to be slowed and brought back up by the elastic band before hitting the ground (we hope). Estimate the length and spring constant of the elastic you would recommend using.
- Estimate the angular momentum an automobile tire has about its axis of rotation while the car is driving on the interstate.
- In testing a design for a yo-yo, an engineer begins by constructing a simple prototype -- a string wound about the rim of a wooden disk. She puts an axle riding on nearly frictionless ball bearings through the axis of the wooden disk and fixes the ends of the axle. In order to measure the moment of inertia of the disk, she attaches a weight of mass m to the string and measures how long it takes to fall a given distance. (a) Assuming the moment of inertia of the disk is given by I, and the radius of the disk is R, find the time for the mass to fall a distance h starting from rest.
(b) She doesn't have a very accurate stopwatch but wants to get a measurement good to a few percent. She decides a fall time of 2 seconds would work. How big a mass should she use? Imagine you were setting up this experiment and make reasonable estimates of the parameters you need. - According to some recent highly accurate measurements made from satellites, the continent of North America is drifting at a rate of about 1 cm per year. Assuming a continent is about 50 km thick, estimate the kinetic energy the continental US has a a result of this motion.
- While on travel this past summer, I passed through Charles deGaulle airport in Paris, France. The airport has some interesting devices, including a "people mover" -- a moving strip of rubber like a horizontal escalator without steps. It became interesting when the mover entered a plastic tube bent up at an angle to take me to the next terminal. I managed to get a photograph of it. It is shown in the figure below. If you were building this people mover for the architect, what material would you choose for the surface of the moving strip? (Hint: You want to be sure that people standing on the strip do not tend to slide down it. Figure out what coefficient of friction you need to keep from sliding down and then look up coefficients of friction in tables in reference books in the engineering library to get a material appropriate for the slipperiest shoes.)[IMG]http://www.physics.umd.edu/perg/fermi/fermim1.gif[/IMG]
- Estimate the angular momentum of the earth due to its daily rotation about its axis. The average density of the earth is about 5 grams/cm3. Estimate the angular momentum of the earth due to its daily rotation about its axis. The average density of the earth is about 5 grams/cm3.
From India, Madras
hi all,
you can have these type of in the following books for reference.
"How Much is a Million" by David Schwartz
"Meta magical Themas" by Douglas Hofstadter
"Innumeracy" by John Allen Paulo's
"Used Math" by Clifford E. Schwartz
"Aha" and "Aha - Gotcha!" by Martin Gardner Thanks
Sundar
From India, Madras
you can have these type of in the following books for reference.
"How Much is a Million" by David Schwartz
"Meta magical Themas" by Douglas Hofstadter
"Innumeracy" by John Allen Paulo's
"Used Math" by Clifford E. Schwartz
"Aha" and "Aha - Gotcha!" by Martin Gardner Thanks
Sundar
From India, Madras
Community Support and Knowledge-base on business, career and organisational prospects and issues - Register and Log In to CiteHR and post your query, download formats and be part of a fostered community of professionals.
Top 10 problems with most Sales people.zip
Home Remedies For Memory Problems.pdf