Magnetic field and transformer
· 1. The electromagnet of Figure has reluctance given by R(x) = 7 x 108(0.002 + x)
H1, where x is the length of the variable gap in meters. The coil has 980 turns and
302 resistance. For an applied voltage of 120 VDC, find:
a. The energy stored in the magnetic field for fr= 0.005 m.
b. The magnetic force for x = 0.005 m.

Ariver flows from north to south at 8 km/h. a boat is to cross this river from west to east at a speed of 20 km/h (speed of the boat with respect to the earth/ground). at what angle (in degrees) must the boat be pointed upstream such that it will proceed directly across the river (hint: find the speed of the boat with respect to water/river)? a 288 b. 21.8 c. 326 d. 30.2

Thermal stresses are developed in a metal when its a) initial temperature is changed b) final temperature is changed c) density is changed d) thermal deformation is prevented e) expansion is prevented f) contraction is prevented

You are making beer. the first step is filling the glass carboy with the liquid wort. the internal diameter of the carboy is 15 in., and you wish to fill it up to a depth of 2 ft. if your wort is drawn from the kettle using a siphon process that flows at 3 gpm, how long will it take to fill?