This simple experiment uses an unusual graph straightening exercise to confirm the parallel axis theorem for an irregular object. Along the way, it estimates experimental values for g and the moment of inertia of a tennis racket. We use Excel to find a 95% confidence interval for the true values.

At our university, students in introductory physics classes perform a laboratory exercise to measure the range of a projectile fired at an assigned angle. A set of photogates is used to determine the initial velocity of the projectile (the launch velocity). We noticed a systematic deviation between the experimentally measured range and the range…

Physics instruction looks different from one classroom to the next; however, the outcome of those classrooms should be one and the same. Students should understand simple concepts and be able to transfer concepts to more complex problems. In this lesson, I would like to show you how I provide students an opportunity to explore their ideas before…

A torsion oscillator is a vibrating system that experiences a restoring torque given by [tau] = -[kappa][theta] when it experiences a rotational displacement [theta] from its equilibrium position. The torsion constant [kappa] (kappa) is analogous to the spring constant "k" for the traditional translational oscillator (for which the restoring force…

In the western half of the United States, fire bombers are not an uncommon sight. During the "fire season," which can extend from June through November, these specially modified aircraft are used to drop fire retardant chemicals or water on wildfires. It can be an entertaining and instructive classroom exercise to use pictures of these…

The flight trajectory of a water rocket can be reasonably calculated if the magnitude of the drag coefficient is known. The experimental determination of this coefficient with enough precision is usually quite difficult, but in this paper we propose a simple free-fall experiment for undergraduate students to reasonably estimate the drag…

Activities are provided for calculating speeds of celestial bodies. These focus on how fast earth rotates on its axis, how fast planets travel around the sun, and how fast the solar system is traveling with the Milky Way. (JN)

Using a physical picture, an expression for the maximum possible transverse velocity and orientation required for that by a linear emitter in special theory of relativity has been derived. A differential calculus method is also used to derive the expression. (Author/KR)

The simple physics behind the mechanism of the toy are explained. Experimental and mathematical steps are given that help in understanding the motion of the doll-pair. The geometry of the setup is described. (KR)

Described is an activity in which students calculate constant velocity using a tape cassette player. The objectives, procedures, graphing directions, and formulas and values needed for the calculations are included. (KR)

Demonstrates several objects rolling down a slope to explain the energy transition among potential energy, translational kinetic energy, and rotational kinetic energy. Contains a problem from Galileo's rolling ball experiment. (YP)

Describes a set of activities designed to help students determine whether walking or running in the rain will keep you drier. Includes a range from simple to sophisticated formulas that attempt to consider a number of variables and some basic laws of physics in the calculations. (TW)

Presents an experiment that measures the acceleration and velocity of a model rocket. Lift-off information is transmitted to a computer that creates a graph of the velocity. Discusses the analysis of the computer-generated data and differences between calculated and experimental velocity and acceleration of several rocket types. (MDH)