ILTS Science: Physics (243) case studies
ILTS Science: Physics (243) · Put your knowledge to work in context.
Science: Physics (243) is the discipline-specific content test in the Illinois Licensure Testing System, used to judge whether a candidate has the physics knowledge and scientific-inquiry skill expected of a beginning physics teacher in Illinois. Candidates typically take it at the end of an educator-preparation program, while adding a physics designation to an existing certificate, or after an out-of-state or career-change route. The ILTS Science: Physics (243) case studies are 5 cases and about 4,568 words.
1Two Pendulum Values for g: Whose Number Goes in the Class Table?
Two lab groups in the same classroom measure g with a simple pendulum during a 50-minute period. Group A hangs a brass bob on a string they measure as 1.000 m, releases it at about 5 degrees, and times 20 oscillations with a photogate, obtaining a period of 2.003 s.
943 words, about 5 min2A Pulley, an Incline, and an Acceleration That Is Too Small
A 2.5 kg wooden block rests on a 30-degree incline and is connected by a light string over a small pulley to a 1.5 kg hanging mass. The pulley is a solid aluminum disk of mass 0.20 kg and radius 5.0 cm, mounted on an axle the students assume is frictionless.
919 words, about 5 min3Extension Cord on a Reel: A 15 A Breaker and a 10 A Cord
A student sets up a demonstration in the school gym: a 1500 W electric kettle rated at 120 V is plugged into a 25 m, 16 AWG extension cord (about 0.013 ohms per metre of conductor) that is still wound on its plastic reel. The branch circuit is protected by a 15 A circuit breaker.
921 words, about 5 min4A Double Slit That Seems Mislabeled
An optics lab uses a helium-neon laser (633 nm), a double-slit slide labeled d = 0.250 mm with slit width 0.050 mm, and a screen 2.00 m from the slide. A student measures from the centre of the first bright fringe on one side of the central maximum to the centre of the tenth fringe on the same side, records 45.5 mm, and divides by 10.
876 words, about 4 min5Stopping Potentials That Give the Wrong Work Function
In a photoelectric-effect lab, students illuminate a cesium cathode (work function 2.10 eV per the tube datasheet) using the 365 nm and 405 nm lines of a mercury lamp, and find the stopping potential by adjusting a retarding voltage until the photocurrent, read on a 1 nA scale, falls to zero. Dark current of about 0.3 nA persists even at large retarding voltages, so 'zero' is judged by eye.
909 words, about 5 min