Last word: Impact

Impact gets a bad rap. Of course, impacts can cause great harm; blows to the head lead to concussions and traumatic brain injuries. Even mild head impacts can generate cumulative brain damage if repeated many times.

But coordinated impacts on strings and membranes create piano concertos and drum solos. You tap on a melon to tell if it’s ripe, and your doctor taps your back to check your lungs. Impacts excite all frequencies of a system, so engineers tap on aircraft wings to predict when they will flutter and on machine tools to find out if they will chatter. We have learned about brain trauma by using MRI to watch the brain respond to light, safe head impacts.

Impact is not just mechanical. We have impact when we uncover knowledge, invent a new tool or affect the course of someone’s career. Such changes in momentum can occur in a single dramatic event or by the accumulation of many small nudges, as long as those nudges are well-timed and consistent. Over the past 17 years my job has been to help MEMS faculty and students achieve impact in their careers. But as Newton said, the forces of impact go both ways, and I revel in the reverberations.