The imprint was made on the window by a sizeable bird—I’m presuming a pigeon—but there was no trace of the bird when I went outside to check. Hopefully, it was just stunned and managed to fly away after a visit to pigeon urgent care.
Question 1: Estimate (i) the momentum and (ii) the kinetic energy of the bird prior to hitting the window.
Question 2: Estimate (i) the force with which it hit the window, (ii) the pressure on the window during impact, and (iii) the wingspan of the bird, given that the wingtip-to-wingtip horizontal distance on the window was about 18 in. (∼46 cm).
Look for the answers online at tpt.aapt.org under “Browse,” at the very end of the current issue.
Fermi Questions are brief questions with answers and back-of-the-envelope estimation techniques. To submit ideas, please email John Adam (jadam@odu.edu).