Newton's third law states that for every action, there is an equal and opposite reaction. By crashing a physics cart into a wall, various crash cushions can be used to reduce the forces experience by the cart.
As shown in Figure 1, a "Speeder Upper" is a pair of disks that are connected by a short rod of much smaller radius. The NSTA science ruler gives you a feel for the dimensions of the Speeder Upper. The disks are 0.5" thick and 2.5" in diameter and are connected by a short 5/16" diameter wood dowel rod. The 3D printer stl file for the disks is provided with this lesson in the event that you want to make a Speeder Upper for use in your physics classroom.
The ideal gas law is commonly seen in the form PV = nRT, where P is the pressure, V is the volume, T is the absolute temperature, n is the amount of the gas in moles, and R is the ideal gas constant. It is a composite form of Boyle's, Charles's, Avogadro's, and Gay Lussac's laws. This law helps to explain how many things work, including bicycle pumps, hot air balloons, pressure cookers, and steam engines, just to mention a few.
Hysteresis can be defined as a lag time in the response of a system to forces placed on the system. The response of the system depends not only on the present magnitude of the force but also on the previous history of the system. From the point of view of mathematics, the response to the force is a double-valued function. This means that one value applies when the force is increasing, while another value applies when the force is decreasing. A graphical plot of force and re
Figure 1 shows a ramp and three distinctly different objects that you will release from rest at the top. Each object will roll downward to the end of the ramp without slipping, resulting in rotational motion. The roll of Gorilla tape has a shape known as an annular cylinder. The can of jellied cranberry sauce is a solid cylinder. The cardboard tube, in contrast to the can, is hollow. All three of these objects will rotate about their central cylinder axis while rolling down the ramp. Each of these three objects has a
Various forms of the sport now known as croquet have been around for centuries. Plastic or wooden balls are struck with a mallet through hoops, called wickets in the United States. The components of a typical croquet set are shown in Figure 1. Very popular in the UK, there is even a World Croquet Federation for those who take the sport seriously. In the United States, it is common to set up croquet as a garden game at graduation and birthday parties. But who would have thought that a croquet ball and mallet equipped with PocketLab Voyager and the PocketL
Rolling resistance is a force that opposes the motion when an object rolls along a surface. There are many examples of objects experiencing rolling resistance: car or bicycle tires on pavement, skateboard wheels on a half pipe ramp, steel wheels on a railroad track, ball bearings in a pulley, bowling balls on a bowling lane, and carts rolling on a dynamics track, just to mention a few. Many factors can affect the magnitude of the forces associated with rolling resistance.
In addition to automobile features that promote road safety, there has been and continues to be a great deal of work on highway features that save lives. An earlier lab entitled Crash Cushion Investigation, submitted by PocketLab, makes use of the PocketLab HotRod to investigate crash cushioning similar to that shown in Figure 1.
What can you do with a PocketLab Mini HotRod, Voyager, five pieces of HotWheels track, and a half-dozen wood blocks about the size of Jenga blocks? How about an experiment in energy conservation! Add CloudLab and you have an environment for your students/lab groups to perform, analyze, document and save their PocketLab lab reports.
This might be an interesting physics PocketLab study! Good for the human body, or not so good?
