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Q$2.$ Explain the principle of ECM as well as self$-$regulating feature of ECM $.$ Write different

configuration of ECM. A through hole of equilateral triangle cross$-$section with side $15$ mm is

made in an iron plate of thickness using ECM process. Find $($i$)$ the time machining for the hole

with $2000$ A current $($ii$)$ percentage change in current if machining time is reduced to $40\%($iii$)$

mass of material removed if $1000$ A current is supply for $30$ s $.$