Can light exert a force to move an object?

24 October 2016
Presented by Kerstin Göpfrich.

Why don't you get thrown backwards when you switch on your torch? Kerstin Gopfrich made her way to the Nanophotonics Centre in Cambridge to find out from Dr. Anna Lombardi. The answer to Matt's question may blow you away...


Nick James, from BAE systems, spoke at the Royal Institute of Navigation conference about navigating through space. He discussed the issue of photon pressure on space-craft and how this small, but significant, force needs to be taken into account on long space journeys; this is a link:

In this words, the force exerted,: "In units it's about nine micronewtons per square metre."

It certainly does push you back but you need a very bright flash light from memory I believe the force is about 1 newton for 500MW

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