The per unit impedance of a circuit element is 0.15. If

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The per unit impedance of a circuit element is 0.15. If the base kV and base MVA are halved, then the new value of the per unit impedance of the circuit element will be ___________

1. 30.3
2. 0.030
3. 0.30
4. 30

Correct Option: C

X_new =	KVA(new)	×	(KV old)²
	KVA (old)		(KV new)²

=	1/2	×	1	× x_old = 2 × 0.15 = 0.30
	1		(1/2)²