Calculate the number 590
NUMBERMANIA: Calculate the number 590 using numbers [9, 1, 5, 5, 58, 531] and basic arithmetic operations (+, -, *, /). Each of the numbers can be used only once.Correct answers: 3
#brainteasers #math #numbermania
Electric motorIn 1904, the first direct current, interpole, electric motor to be patented in the U.S. was issued to Mathias Pfatischer of Phildadelphia, Pennsylvania under the title "Variable Speed Motor" (No.775,310). His improvement was to "effect commutation without sparking, with a variable load as well as at variable speed and which is capable of rotation in either direction." The new design added auxiliary-field pole-pieces which were small as compared to the main pole-pieces.« |