Electrical Machines The demagnetising component of armature reaction in a DC generator results in sparking trouble. reduces generator emf. reduces inter poles flux density. increases armature speed. results in sparking trouble. reduces generator emf. reduces inter poles flux density. increases armature speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft of induction motor may be unbalanced due to poor lubrication. overheating of winding. uneven air gap. overload. poor lubrication. overheating of winding. uneven air gap. overload. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 541.67V, 200 rpm. 2166.67V, 270 rpm. 541.67V, 250 rpm. 2166.67V, 230 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 541.67V, 250 rpm. 2166.67V, 230 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Exciting current of an induction motor is none of these. higher than power transformer. equal as power transformer. lesser than power transformer. none of these. higher than power transformer. equal as power transformer. lesser than power transformer. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a dc machine shunt resistance and armature resistance values are low and low high and high high and low low and high low and low high and high high and low low and high ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a polyphase induction motor helps to reduce the chance of cogging. increase the starting torque. reduce the magnetizing current. reduce the chance of crawling. reduce the chance of cogging. increase the starting torque. reduce the magnetizing current. reduce the chance of crawling. ANSWER DOWNLOAD EXAMIANS APP