There are two approaches that the teacher can take to doing this experiment on centripetal acceleration with a three-speed ceiling fan and PocketLab.
This lesson is a physics application of PocketLab that allows students to determine the radius of curvature of a gradual turn on a street. A PocketLab mounted on the dashboard of a car records both the angular velocity and the centripetal acceleration of the car as it moves at a nearly constant speed around the curve. All of the required data for an example problem are contained in files attached to this lesson. Alternately, students can collect their own data. If the latter approach is used, students should be cautioned to be safe: (1) follow all speed limits and traffic laws, and (2)
Yes, that's right--the physics of a falling and unrolling toilet paper roll. This experiment will give students practice in rotational motion of an object and translational motion of its center-of-mass. It will also involve both the kinematics and dynamics of the motion. While it can be done by use of the VelocityLab app, interpretation of the angular velocity data from the PocketLab app is much easier.
This experiment is designed for AP Physics and college physics students. It considers a solid cylinder of mass M and radius R that is rolling down an incline with a height h without slipping. Using energy and dynamics concepts, students first derive equations for (1) the speed of the center of mass of the cylinder upon reaching the bottom of the incline, and (2) the acceleration of the center of mass of the cylinder as it rolls down the incline. The free-body diagram at the center shows all forces acting on the cylinder as it rolls down the incline.
The yo-yo, a toy with an axle connected to two disks and string wound on the axle, has been of fascination to many for centuries. It also offers a perfect opportunity to study angular velocity when a PocketLab has been attached to it. A graph of angular velocity vs. time of a yo-yo will require students to think carefully about the detailed behavior related to its motion.
There is a well-known problem in rotational dynamics that involves a meter stick. The meter stick is held in a vertical position with one end on the floor. It is then released so that it falls to the floor. The end initially on the floor is not allowed to slip during the fall. Students are asked to derive an equation that predicts the angular velocity of the meter stick just before it hits the floor. The derivation involves many physics concepts including gravitational potential energy, rotational kinetic energy, conservation of energy, moment of inertia, and angular velocity, thus giv
Most everyone has spun a coin on its edge on a table top, and many find the result quite fascinating. The coin gradually begins to fall on its side while spinning, makes a whirring sound with increasing frequency the longer it spins, and then abruptly stops. The Swiss physicist, Leonhard Euler, studied this back in the 1700's. An educational toy, referred to as Euler's disk can now be purchased on-line and in hobby shops specializing in science. Such disks have been carefully engineered to spin for a much longer time than a coin.
Exploration
The moment of inertia (MOI) is the rotational inertia of an object as it rotates about a specific axis. Moment of inertia determines the torque required for a specific angular rotation about an axis. The moment of inertia depends upon the distribution of mass of the rotating object in relation to the axis the object is rotating about.
Objective
Exploration
The moment of inertia (MOI) is the rotational inertia of an object as it rotates about a specific axis. Moment of inertia determines the torque required for a specific angular rotation about an axis. The moment of inertia depends upon the distribution of mass of the rotating object in relation to the axis the object is rotating about. Explore whether the stability of a book’s rotation is dependent upon the moment of inertia and therefore whether it changes based on the axis the book is rotating about.
Objective
Exploration
An inertial force arises from the rotation of the object and the object mass (sometimes called the centrifugal force, not to be confused with centripetal force). If the inertial force is greater than the force of friction, the object will slide off of the rotating turntable (following Newton’s First Law of Motion). The parameters that cause the inertial force to be greater than the force of friction depend on many variables.
Objective
