DC Shunt Motors: Numerical problems on Armature Torque & Shaft Torque

[@nityasunil9356]

Thankyou sooo muchhhhh i am literally crying. Thankyou plz keep making more of such vids. Very helpful. Thankyou so much.

[@gargibasu5111]

Most welcome 😊

[@mugdhoandmusic2995]

mam,you are excellent,plz make such a useful video more so that i can solve all problem

[@gargibasu5111]

Sure I will

[@josephguida5432]

Hello Mam. I really like problem #2. I assumed 2 circuit to mean 2 parallel paths. I learned a great deal from you.

[@gargibasu5111]

Glad to be helpful.

[@skyhyrevamonte4189]

Can you help how to solve it maam😁 A 300V DC shunt motor, shunt resistance (150 Ω), armature resistance (0.2 Ω), the source supplied current equal to 36 A, core losses (210 W), running at 1500 r.p.m., friction losses (100 W). Find: (a) back e.m.f. , (b) efficiency, (c) developed torque, (d) shaft torque.

[@gargibasu5111]

V=300volts;Ish=300/150=2A;Ia=36-2=34A; back emf, Eb=300-34*0.2=293.2volt

[@gargibasu5111]

Developed power, Pd=Eb*Ia=293.2*34=9968.8W Output power, Po=Pd-losses=9968.8-(210+100)=9658.8W Input power, Pin=VI_L=300*36=10800W Efficiency =Po/Pin=9658.8/10800=89.43% Developed torque Td=Pd/(2*pi*1500/60)=63.46N-m Output torque Tsh=Po/(2*pi*1500/60)=61.4898N-m