Assessing the perineum for bulging is a nursing priority to a client at the second labor stage. A bulging perineum is caused by the presence of the fetal head against the perineal area and usually signifies imminent birth. Pain medication is not administered this close to the birth instead it crosses the placenta barrier and can cause respiratory distress in the newborn. During this second stage of labor the client is encouraged to push, not pant, with each contraction.
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Answer:
this is because Steel is more difficult to magnetise and demagnetise but an iron core makes a temporary electromagnet because its lose its magnetism when the switch is open and and steel core is used to make a permanent electromagnet
