Breaking News
Comments
Newest First | Oldest First | Threaded View
Page 1 / 2   >   >>
chinapope2007
User Rank
Author
re: Can you solve this brainteaser?
chinapope2007   3/1/2008 12:15:09 AM
NO RATINGS
Hello everyone. No offense at first. It may not be such simple as we thought. What means a "brainteaser" ?

cPaulButler
User Rank
Author
re: Can you solve this brainteaser?
cPaulButler   2/29/2008 5:11:46 PM
NO RATINGS
When I first saw this, I was surprised that the answer is independent of the starting circumference. It's interesting that the answer is surprising, since I'm not surprised that circumference is proportional to radius. Maybe that means that the distributive property of multiplication is nonintuitive. I doubt the explanation is that simple, since another form of the question doesn't seem to be a riddle at all: A company pays each of its employees $6.28 per hour, for a total of $40,000 per hour. How much more would the company need to spend per hour to hire one more employee? C = 2*pi*R R' = R+1 C' = 2*pi*(R+1) = 2*pi*R + 2*pi = C + 2*pi Paul

Controller Freak
User Rank
Author
re: Can you solve this brainteaser?
Controller Freak   2/28/2008 7:01:19 PM
NO RATINGS
Try that again: The circumference is just over 40,000 km. I better give up :).

ben mcm
User Rank
Author
re: Can you solve this brainteaser?
ben mcm   2/28/2008 7:00:01 PM
NO RATINGS
on a completly different tangent: the string would stretch the extra approx. 2m as the requirement didn't specify tension to remain the same.

Controller Freak
User Rank
Author
re: Can you solve this brainteaser?
Controller Freak   2/28/2008 6:59:28 PM
NO RATINGS
Correction, I confused diameter with circumference. The diameter comes out to just over 40,000 km.

Controller Freak
User Rank
Author
re: Can you solve this brainteaser?
Controller Freak   2/28/2008 5:27:47 PM
NO RATINGS
I don't think any extra string is required. You already have 40,000 kilometers worth, which is way more than enough to encircle the earth.

Ironman2
User Rank
Author
re: Can you solve this brainteaser?
Ironman2   2/28/2008 5:06:25 PM
NO RATINGS
If string is lifted 1m, effective diameter increases by 2m. let d = 2meters. If D is original diameter then difference in circumference is C = (Pi*(D+d) - Pi*D) = Pi*d = 2*Pi meters = 6.283 meters

RickB45
User Rank
Author
re: Can you solve this brainteaser?
RickB45   2/28/2008 2:41:52 PM
NO RATINGS
If we assume a perfect circle of string then we can calculate the Diameter D C=Pi x D D=C/Pi = 40x10^6/Pi When you lift the string by 1 Meter, the diameter increases by 2 Meters. Then all you need to do is calculate the new circumference C and take the difference between old and new. NewC=(C/Pi + 2) x Pi To get the difference: Difference = NewC ? C = [(C/Pi + 2) x Pi ] ? C. = C + 2xPi ? C = 2xPi The answer I get is 2xPi Rick.

hzulu
User Rank
Author
re: Can you solve this brainteaser?
hzulu   2/28/2008 12:32:12 PM
NO RATINGS
It would be interresting how this equation looks, which gives the result how far we have to move to north or south... A real topic for my math teacher, who teased me with such questions back in school some decades ago.

chinapope2007
User Rank
Author
re: Can you solve this brainteaser?
chinapope2007   2/28/2008 11:07:10 AM
NO RATINGS
NO extra string needed to fill the gap if we could move our position towards southpole or northpole a little.

Page 1 / 2   >   >>


Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Like Us on Facebook
Special Video Section
Protecting sensitive electronic circuitry from voltage ...
09:45
Watch as a web server authenticates or rejects a water ...
Protecting sensitive electronic circuitry from voltage ...
Watch as a web server authenticates or rejects a water ...
Protecting sensitive electronic circuitry from voltage ...
Power can be a gating factor in success or failure of ...
Get to market faster and connect your next product to the ...
00:44
See how microQSFP is setting a new standard for tomorrow’s ...
The LTC3649 step-down regulator combines key features of a ...
Once the base layer of a design has been taped out, making ...
In this short video we show an LED light demo to ...
The LTC2380-24 is a versatile 24-bit SAR ADC that combines ...
In this short video we show an LED light demo to ...
02:46
Wireless Power enables applications where it is difficult ...
07:41
LEDs are being used in current luxury model automotive ...
With design sizes expected to increase by 5X through 2020, ...
01:48
Linear Technology’s LT8330 and LT8331, two Low Quiescent ...
The quality and reliability of Mill-Max's two-piece ...
LED lighting is an important feature in today’s and future ...
05:27