Final answer:
The property of a coil to oppose any change in the current flowing through it is called self-inductance, which is governed by Lenz's Law and is measured in henries (H).
Step-by-step explanation:
The property of a coil to oppose any change in the current flowing through it is called self-inductance. This opposition is a result of Lenz's Law, which states that the direction of the induced electromotive force (emf) will always oppose the change in magnetic flux that causes it. Hence, when there is a change in current within a coil, the coil counters by producing its own emf to resist this change. Self-inductance is measured in units of henries (H). A coil with a high self-inductance, such as a large coil with many turns and an iron core, will significantly oppose changes in current, making it difficult for the current to change rapidly. On the contrary, smaller self-inductance can be achieved by counterwinding coils in order to permit faster changes in current.