Physics for Biologists Gravity Defying Creatures Lab 4-Cuyamaca College .
Name: Physics for Biologists Lab 4: Gravity defying creatures __________________________________________________________________________ Overview ● Why is it that some creatures seem to defy gravity? ● How do all these components work together to achieve a stable and high-performing rocket? Theory ● Newton’s second law: F = ma ● Friction ● Freebody diagrams ______________________________________________________________________________ Creature 1: The Gecko 1. Draw a freebody diagram including all forces on the gecko above walking standing still on the surface of a vertical wall. 2. Do some investigating and find the approximate mass of a gecko in SI units. If you cannot find the mass in SI units then convert it. 3. Using this mass, determine the amount of force that each foot must generate in order to support its weight. 4. Research: Using online articles or videos, help crack the code for how Geckos are so good at what they do. What is the biophysical mechanism for their ability to walk on walls? Draw a microscopic picture to demonstrate your understanding. 5. The mechanism for how geckos do their walk has to do with something called Van der Waals forces. What are these forces and how do they work? Physics 190 Scott Stambach Cuyamaca College Creature 2: Black widows 1. Draw a freebody diagram including all forces on the spider standing still upside down on a horizontal ceiling. 2. Do some investigating and find the approximate mass of a black widow in SI units. If you cannot find the mass in SI units then convert it. 3. Using this mass, determine the amount of force that each foot must generate in order to support its weight. Physics 190 Scott Stambach Cuyamaca College 4. Research: Using online articles or videos, help crack the code for how spiders are so good at what they do. What is the biophysical mechanism for their ability to walk on walls? Is it unique to that of the geckos? 5. According to your research, how many times their own body weight can spiders safely hold while walking on walls. Physics 190 Scott Stambach Cuyamaca College Creature 3: Gerridae 1. Draw a freebody diagram including all forces on the Gerridae insect above standing on the surface of a pond water. 2. Do some investigating and find the approximate mass of a Gerridae in SI units. If you cannot find the mass in SI units then convert it. Physics 190 Scott Stambach Cuyamaca College 3. How much normal force must the water apply to each of the Gerridaes legs in order to get him to be able to stand on water? 4. Research: How does this work? How does the water generate enough normal force for the Gerridae to stand? Why does this not work with humans? Physics 190 Scott Stambach Cuyamaca College
