PIRA Code(s): 1D60.20 Set up time:5 minutes Operation: Mount apparatus to ring stand using clamp, adjust until apparatus is horizontal, cock the apparatus spring, and place the masses (one at the end of the apparatus and one on the bar that extends from the apparatus), release, and one ball will fall from rest (hung on the rod) while the other ball is struck by the rod and has an initial horizontal velocity. The balls should hit the table at the same time, which can be heard clearly by students. Repeat by cocking spring to different compression. Repeat by clamping apparatus at a different height to show that height has no effect on the simultaneity of the fall. Physics and Science Concepts: Projectile Motion Safety: Once spring is compressed, do not put hands in front of the end of the rod.
PIRA Code(s): 1M20.10 Set up time:none Operation: These may be used by themselves or with other demonstrations. Physics and Science Concepts: Mechanics, Mechanical Advantage, Simple Machines Safety: None
PIRA Code(s): 1M20.30 Set up time:5 minutes Operation: Set the empty friction box on the incline with weights attached to the string on the other side of the pulley so that the box slides forward. Then, gradually increase the angle of the plane until the box and the weights reach equilibrium. Physics and Science Concepts: Equilibrium of forces, Mechanics, Work and Energy Safety: None
PIRA Code(s): 1M40.20 Set up time:none Operation: Place ball at the top of track and let it fall. To show students the minimum height required to loop the loop, place the ball on the track at a height that is about double the height of the loop. Physics and Science Concepts: Mechanics, Work and Energy, Conservation of Energy, Centripetal Force Safety: Do not stand where the ball exits the track.
PIRA Code(s): 3A10.20 Set up time:1 minute Operation: Move the weight along the hacksaw blade. Pull back on the blade and release. When the weight is at the top of the blade the frequency is smaller compared to when the weight is at the bottom. Physics and Science Concepts: Oscillations Safety: Edge of blade may be sharp.
PIRA Code(s): 4A30.20 Set up time:2 minutes Operation: Try putting the ring around the ball. At room temperature the ring is slightly larger than the ball. Heat the ball over a Bunsen burner and it will no longer fit through the ring. Physics and Science Concepts: Thermodynamics, Thermal Properties of Matter, Thermal Expansion Safety: Use caution when using a Bunsen burner. The Bunsen burner is not included in the experiment.