A) 7 A
B) 3 A
C) 5 A
D) 4 A
Correct Answer: A
Solution :
[a] Let initial e.m.f. induced =e \[\therefore \] Initial current \[i=\frac{E-e}{R}\] i.e., \[2=\frac{12-e}{1}\] This gives \[e=12-2\text{=}10\] volt. As \[e\propto \omega \]. when speed is halved, the value of induced e.m.f. becomes \[\frac{e}{2}=\frac{10}{2}=5\,volt\] \[\therefore \] New value of current \[i'=\frac{E-e}{R}=\frac{12-5}{1}=7A\]You need to login to perform this action.
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