Electrical Machines A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.25 p.u 0.125 p.u 0.75 p.u 0.5 p.u 0.25 p.u 0.125 p.u 0.75 p.u 0.5 p.u ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The maximum possible speed at which an alternator can be driven to generate 50 Hz and 4000 V is 3600 rpm. 3000 rpm. 1500 rpm. 4000 rpm. 3600 rpm. 3000 rpm. 1500 rpm. 4000 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A delta/star transformer is connected in parallel to a star/delta transformer. The turn ratio former is x times latter, the x is 1/3 1/√3 3 √3 1/3 1/√3 3 √3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The squirrel cage induction motors are provided with blades in order to none of these. eliminate noise. facilitate cooling of rotor. balance the rotor dynamically. none of these. eliminate noise. facilitate cooling of rotor. balance the rotor dynamically. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines internal characteristics are plotted between Vt vs load current Eg vs Ia Vt vs Ia Eg vs load current Vt vs load current Eg vs Ia Vt vs Ia Eg vs load current ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The DC generator runs at a speed of 1000 rpm and flux per pole is 0.2 Wb, number of poles are 2 the winding is wave wound and having 480 conductors. The critical speed is 1200 rpm. Then the generated emf ( Eg ) 0 Volt. 2000 Volt. 1500 Volt. 1600 Volt. 0 Volt. 2000 Volt. 1500 Volt. 1600 Volt. ANSWER DOWNLOAD EXAMIANS APP
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