The sum of odd. Effective trick and its solution

EFFECTIVE FOCUSES AND THEIR CLUES
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The sum of odd. Focus Secret

Spectacular tricks and their clues

Directory / Spectacular tricks and their clues

Focus Description:

Ask the viewer to calculate the sum of all odd numbers from 1 to 0 in 20 minute (without a calculator). He most likely won't make it. Speak:

- Well, you and the turtle, try again, just live, what is the sum of the odd ones from 0 to 45 inclusive?

Most likely, the viewer will dismiss it, saying that I couldn’t do it up to 20, but here it’s up to 45 (here it’s already possible with a calculator, but again, it’s limited in time so that it doesn’t have time). You easily count the sum of all odd, even multi-digit numbers (only who will check)

Focus secret:

It is necessary to add 1 to the last (given) odd number, divide by 2 and square it.

Example: from 1 to 49 inclusive 49+1=50, 50/2=25, 25*25=625.

If you are asked to count a very large number, then you will still have to use a calculator, but since it is very small, you will do it in 10-15 seconds.

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Microgravity is helping to provide answers and models for improving the processes needed to efficiently burn solid fuels such as iron dust. Solid propellants are used to burn matches, to light sparklers on New Year's Eve, and as fuel in the boosters of many rockets.

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The technology has the potential to reduce greenhouse gas emissions globally, but an obstacle to the implementation of this technology is the development of combustion systems that can efficiently burn metallic fuels, which requires a solid understanding of the physics of their combustion.

In order to understand the physics of metallic fuel combustion, the iron powder cluster must be suspended for about 30 seconds, the time needed to observe and study how the flame spreads. Researchers have used sounding rockets and parabolic flights to conduct weightlessness experiments and test existing models, with promising results. The density of iron particles and the composition of gases in the combustion chamber are important parameters, as in a gasoline car engine.

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