I was taught that if you want to change the direction of a three phase rotating machine that is rotating in forward direction, you interchange the phases. Since the phases has the same features (voltage and current), what is responsible for making the machine to rotate in reverse direction, when the phases are interchanged?


Question: Which definition is more used for "determine"?
Answer: The second sense of determine is not “to forecast or predict”, but rather to “find out by investigation, reasoning, or calculation”, sense 4 in Merriam-Webster. Merriam-Webster gives other examples of this sense: “&lt;determine the answer to the problem&gt; &lt;determine a position at sea&gt;”.

If we take a look at the first ten results in newspapers for determine in the Corpus of Contemporary American English, we see this sense occurs in six of them:


jobs. // And so we acted robustly. And now it's time to determine whether or not this pro-growth package will actually work. // The checks will start  
onto Floor 10 -- - incognito, of course -- - and set out to determine whether it was truly what women want. // You know: Mirrors that make  
astronomy. Its original mission was to find a way for sailors at sea to determine longitude. Unlike latitude, which uses the equator as a starting position, there  
Sharpton stood with members of Officer Ridley's family and called for an investigation to determine whether the shooting was justified. //' Just as we are calling on the  
// Win or lose -- and the status of West's sore back could largely determine the outcome -- the future in New Orleans appears bright. The core players --  
, they lifted all sanctions. // Whether Clayton can do that hard work could determine if Flenoury can go to one of his two choice schools, Georgia or Duke  
worked with Kerviel was released after being questioned. Two investigating judges are trying to determine what, if anything, Kerviel's colleagues and superiors knew about his unauthorized trades  
because of my race? Sure. " // He doesn't think race will determine who wins the election, however. Obama said most voters will make their choice  
confluence within the monument boundary, so right now Dinosaur is an incredible lab to determine the impact dams have on rivers. " // Kleinschnitz, who started rowing the  
fight and every team gives it -- for a while. But early results can determine where a team keeps fighting all season and how confidently it battles in the close  


The only uses which are not the sense meaning “to find out” are #5, #6, #8, and #10. So, from this admittedly small sample it does appear that both senses enjoy approximately equally robust usage.