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Hi, this problem is bugging me for several days now. In ”200 Puzzling Physics Problems”, Gnadik, Honyek, Riley there is this Problem 59:

this would lead to α=1/2, β=-1/2 and γ=-δ=k. So, we'll get for the rotor speed

http://www.educatiarutiera.ro/wp-content/uploads/2017/03/sol591.png [Broken]

Please let me know wether my reasoning is correct. I'm not familiar with dimensional analysis and I'd really want to introduce this problem to some of my students. Thank you.

The solution to this is an ingenious resort to dimensional analysis, as follows:A helicopter can hover when the power output of its engine is P. A second helicopter is an exact copy of the first one, but its linear dimensions are half those of the original. What power output is needed to enable this second helicopter to hover?

Now, I don't have a problem with this. I wonder however, what if we express, instead of the power needed to hover, the rotor speed, or frequency, that has the dimension shttp://www.educatiarutiera.ro/wp-content/uploads/2017/03/sol59.png [Broken]

^{-1}.this would lead to α=1/2, β=-1/2 and γ=-δ=k. So, we'll get for the rotor speed

**, needed for the helicopter to hoover:***s*http://www.educatiarutiera.ro/wp-content/uploads/2017/03/sol591.png [Broken]

Please let me know wether my reasoning is correct. I'm not familiar with dimensional analysis and I'd really want to introduce this problem to some of my students. Thank you.

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