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Exciting examples of physics principles illuminate the power and scope of our discipline. In this paper, we discuss a conservation of energy example for an introductory course. Energy conservation is applied to bird and dinosaur eggs to derive a method to predict the incubation period and the embryonic metabolism solely from the egg geometry. The power of this fundamental principle to yield insights into a biological example helps to demonstrate the utility of conservation of energy.

The article explores the metabolic rates of non-avian dinosaurs, crocodiles, and birds during embryonic development by calculating the activation energy of their metabolic reactions. The study uses conservation of energy principles and the Boltzmann factor to determine how metabolism changes with temperature. Results show that birds had the highest metabolism in the egg, with Troodon dinosaurs having the highest metabolism among the three dinosaur species studied. The findings suggest a link between metabolic rate and incubation temperature, with implications for sex determination in crocodilians. [Extracted from the article]

Most physics courses begin with one-dimensional kinematics, which is usually restricted to the case of constant acceleration. Here we report a unique exercise for an introductory algebra-based physics course involving the running and non-constant acceleration of the theropod dinosaur "Dilophosaurus wetherilli" and the world-famous Jamaican sprinter Usain Bolt. Given the interest that most students have about dinosaurs (as well as Usain Bolt), students are excited to examine a hypothetical 100-meter race between "Dilophosaurus" and Usain Bolt. Since these students have not yet taken calculus, and as part of our effort to build computational skills in our students, numerical methods are used via a spreadsheet to calculate displacements and accelerations numerically from velocity data. This work includes a discussion of uncertainties.

Igniting excitement for physics in our students is a goal of every instructor. In this paper, we discuss a unique example of the concept of density, a subject that is rarely viewed as intriguing by students. By combining a problem involving dinosaurs and an effective density, our students' interest is often captured through calculating an estimated mass of hatchling tyrannosaur and sauropod dinosaurs. This unusual kind of density also provides an interesting backdrop for students to test their understanding of density. We also discuss how this result can be used to learn more about dinosaurs.

Open-ended problems are a very effective tool for engaging student interest. In this paper, we report a physics activity that provides insight into the lifestyle of theropod dinosaurs. This activity generates great enthusiasm among the students since virtually everyone is interested in dinosaurs. In the spirit of the "spherical cow" approach to difficult problems, we consider the problem at the simplest level. This type of approach is very important since it helps students learn how to estimate answers for many "real-world" problems. At the end of the activity, we discuss how the calculations could be improved by including more effects.

In this paper, we examine a first-year torque and angular acceleration problem to address a possible use of the forelimbs of "Tyrannosaurus rex." A 1/40th-scale model (see Fig. 1) is brought to the classroom to introduce the students to the quandary: given that the forelimbs of "T. rex" were too short to reach its mouth, what function did the forelimbs serve? This issue crosses several scientific disciplines including paleontology, ecology, and physics, making it a great starting point for thinking "outside the box." Noted paleontologist Kenneth Carpenter has suggested that the forelimbs of "T. rex" were an integral part of its predatory behavior. Given the large teeth of "T. rex," it is assumed that they killed with their teeth. Lipkin and Carpenter have suggested that the forelimbs were used to hold a struggling victim (which had not been dispatched with the first bite) while the final, lethal bite was applied. If that is the case, then the forelimbs must be capable of large angular accelerations a in order to grab the animal attempting to escape. The concepts of the typical first-year physics course are sufficient to test this hypothesis by solving a = t/I. Naturally, students love solving any problem related to "Tyrannosaurus rex"!

The article discusses the application of Newton's law of cooling to the earliest horse species, Sifrhippus sandrae, during the Paleocene-Eocene thermal maximum. It explores how the size of Sifrhippus changed in response to environmental temperature fluctuations, highlighting the correlation between body size and ambient temperature in various species. The study uses Newton's law of cooling to evaluate heat loss per unit body mass of Sifrhippus in warm and cool environments, showing that the cooling power per unit mass remained consistent across different temperatures. The research suggests that the size of Sifrhippus was influenced by environmental temperature, with alternative explanations such as food availability being less likely. [Extracted from the article]

In the second paper of this series, the effect of transverse femoral stresses due to locomotion in theropod dinosaurs of different sizes was examined for the case of an unchanging leg geometry. Students are invariably thrilled to learn about theropod dinosaurs, and this activity applies the concepts of torque and stress to the issue of theropod locomotion. In this paper, our model calculation of Ref. 1 is extended to incorporate the fact that larger animals run with straighter legs. As in Ref. 1, students use geometric data for the femora of theropod dinosaurs to analyze their locomotion abilities. This can either be an in-class activity or given as a homework problem. Larger theropods are found to be less athletic in their movements than smaller theropods since the stresses in the femora of large theropods are closer to breaking their legs than smaller theropods.

Finding topics that inspire students is an important aspect of any physics course. Virtually everyone is fascinated by "Tyrannosaurus rex," and the excitement of the class is palpable when we explore scaling effects in "T. rex" and other bipedal theropod dinosaurs as part of our discussion of mechanics and elasticity. In this paper, we explore the role of longitudinal stress in the femur bones due to the weight of the dinosaur in determining how the geometry of the femur changes with size of the theropod. This is one area of allometry, the study of how different biological characteristics scale with size.

Conservation of energy is one of the foundations of science, and in this paper, we use this principle to estimate the resting breathing rate of the dinosaur Plateosaurus trossingensis (see Fig. 1). Animals produce the energy necessary for life via chemical reactions in which biomolecules (such as glucose) react with oxygen to release CO2, H2O, and energy. The metabolism is determined from the animal's reported mass growth curve (the mass of the animal as a function of age during its juvenile growth) using a model based on conservation of energy. The metabolism reveals the rate at which oxygen is used by the animal. The efficiency of oxygen extraction is assumed to be the same as observed in modern birds (which have a very efficient "one-way" breathing modality and are direct descendants of dinosaurs). Using the estimated concentration of oxygen in Earth's atmosphere during the Late Triassic period yields the amount of air that P. trossingensis breathed each minute. Finally, the tidal volume (the volume of air inhaled in each breath) was used to calculate its resting breathing rate. This exercise has been used in introductory and intermediate courses on thermal physics, and the students find it empowering (and fun) to be able to gain this insight into the physiology of a dinosaur. [ABSTRACT FROM AUTHOR]