A 25 ℎ𝑝, 250 𝑉 dc series motor has armature resistance of 0.1 Ω, field resistance of 0.05 Ω and brush contact drop 3 𝑉. When the line current is 80 𝐴, the speed is 600 rpm and when the line current is 100 𝐴, the speed will be nearly:
A. 394 rpm
B. 474 rpm
C. 556 rpm
D. 636 rpm
Answer:B
A 25 ℎ𝑝, 250 𝑉 dc series motor has armature resistance of 0.1 Ω, field resistance of 0.05 Ω and brush contact drop 3 𝑉. When the line current is 80 𝐴, the speed is 600 rpm and when the line current is 100 𝐴, the speed will be nearly:
A. 394 rpm B. 474 rpm C. 556 rpm D. 636 rpm