Ann-Marie Pendrill

Acceleration and Rotation in a Pendulum Ride, Measured Using an iPhone 4.

Many modern cell phones have built-in sensors that may be used as a resource for physics education. Amusement rides offer examples of many different types of motion, where the acceleration leads to forces experienced throughout the body. A comoving 3D-accelerometer gives an electronic measurement of the varying forces acting on the rider, but a complete description of a motion also requires measurement of the rotation around the three axes, as provided, for example, by the iPhone 4. Here we present and interpret accelerometer and gyroscope data that were collected on a rotary pendulum ride.

Classical physics experiments in the amusement park

An amusement park is a large physics laboratory, full of rotating and accelerated coordinate systems. The forces are experienced throughout the body and can be studied with simple equipment or with electronics depending on age and experience. In this paper, we propose adaptations of classical physics experiments for use on traditional rides.

Swings and slides

The use of playground rides as teaching tools is discussed with the emphasis being on slides and swings. A variety of different aspects of physics are covered including force, acceleration, friction, electrostatics and reflection. The physics content would be applicable to most age groups at some level.

The Equivalence Principle Comes to School--Falling Objects and Other Middle School Investigations.

Comparing two objects falling together is a small-scale version of Galileo’s classical experiment, demonstrating the equivalence between gravitational and inertial mass. We present here investigations by a group of ten-year-olds, who used iPads to record the drops. The movie recordings were essential in the follow-up discussions, enabling the students to compare the different situations and to discern situations where air resistance was essential and where it could be neglected. By considering a number of familiar situations and simple investigations that can be performed, e.g., on a playground, students may come closer to an appreciation of the deep significance of the non-influence of mass on motion under gravity.

Rollercoaster loop shapes

Many modern rollercoasters feature loops. Although textbook loops are often circular, real rollercoaster loops are not. In this paper, we look into the mathematical description of various possible loop shapes, as well as their riding properties. We also discuss how a study of loop shapes can be used in physics education.

Experimental and theoretical investigation of the isotope shift of the 4D level in atomic potassium

Doppler-free two-photon laser spectroscopic measurements in the deep red spectral region have been performed on the transition 42S1/2→42DJ in the naturally abundant isotopes 39 and 41 of atomic potassium. The 4D level isotope shift, −81±12 MHz was obtained by combining the current results with data from Rydberg-state spectroscopy.Many-body perturbation theoretical calculations of the specific mass shift in the measured state are also presented. With the use of Brueckner orbitals the value −70 MHz was obtained in substantial agreement with the experimental result.

Student Investigations of Forces in a Roller Coaster Loop.

How does the experience of a riding in a roller coaster loop depend on your position in the train? This question has been investigated by first year engineering physics students by using multiple representations of force and motion. Theoretical considerations for a circular loop show that the differences between the forces on a rider in the front, middle or back of the train depend on the ratio between train length and radius of the loop, which can be estimated from a photograph. Numerical computations complement the analysis of a video clip, accelerometer data, and measurements of the time needed for the train to move over the highest point. A roller coaster ride gives striking examples of Newtons laws applied to your own body, and demonstrates that the experience depends on the vector character of velocity and acceleration.

Beyond velocity and acceleration: Jerk, snap and higher derivatives

The higher derivatives of motion are rarely discussed in the teaching of classical mechanics of rigid bodies; nevertheless, we experience the effect not only of acceleration, but also of jerk and snap. In this paper we will discuss the third and higher order derivatives of displacement with respect to time, using the trampolines and theme park roller coasters to illustrate this concept. We will also discuss the effects on the human body of different types of acceleration, jerk, snap and higher derivatives, and how they can be used in physics education to further enhance the learning and thus the understanding of classical mechanics concepts.

Motion on an Inclined Plane and the Nature of Science.

Friction is an important phenomenon in everyday life. All children are familiar with playground slides, which may thus be a good starting point for investigating friction. Motion on an inclined plane is a standard physics example. This paper presents an investigation of friction by a group of 11-year olds. How did they plan their investigations? What aspects of friction could they discern? What understanding of the nature of science was revealed—and developed—during their investigation and subsequent discussion with the teacher?

How do we know that the Earth spins around its axis

A carousel gives possibilities to explore physics in rotating systems and to gain first-hand experience of methods to measure rotation, without the need for an external reference. This paper discusses the Foucault pendulum, as well as the sideways deflection of horizontally and vertically moving objects in a rotating system. These experiments lay the foundation for an understanding of ways to demonstrate that the Earth spins around its axis.