For a series circuit, the impedance equals the resistance plus the reactive inductance.

\(\text {Inductive Reactance (ohms)} = 2\Pi FL \Tiny \text { Where F is frequency in Hertz (Hz) & L is inductance in (Henrys)}\\ 2\Pi (10 kHz) \times (50mH) = 3.142k \varOmega \\ {3142 \varOmega + 1000\varOmega = 4142 \; \varOmega \; or \; 4.142K\varOmega } \)

You started off correctly, Guest, but series impedances don't add algebraically, they add according to Pythagoras.

So impedance Z = [(X_L )² + R² ]^½

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