Series motor takes (80 A) on full-load voltage (400 V) and runs at (1000 r. p.m) the armature resistance is (0.2 Q) and the series winding resistance is (60 m2). 1- Determine the resistance to be connected in series to reduce the speed to (700 r. p.m) with same current. 2- Determine the speed when developing full load torque but with a (0.15 ) diverter in parallel with the field winding.​

The higher the astm grain-size number, the coarser the grain is. a)-true b)-false

Apipe with an outside diameter of 15 cm is exposed to an ambient air and surrounding temperature of -20°c. the pipe has an outer surface temperature of 65°c and an emissivity of 0.85. if the rate of heat loss from the pipe surface is 0.95 kw per meter of length, the external convective heat transfer coefficient (h) is: (a) 12.5 w/m"k (b) 18.6 w/mk (c) 23.7 w/mk (d) 27.9 w/mk (e) 33.5 w/mk

True or false (explain) (110)[111] is a slip system in bcc metals . the {111} family in fcc contains 8 planes. resolved shear stress (rss) in single crystals is just related to the applied stress. critical resolved shear stress (crss) in single crystal metals is direct proportional to the number of defects in the structure