PIRA 200
Modern Physics


MODERN PHYSICS

7A10.10

QUANTUM EFFECTS

Photoelectric Effect

Discharging Zinc Plate

 

A polished zinc plate sits atop an electroscope. Charge the electroscope with a rod. Turn on the UV light. Removed the protective glass plate to expose the zinc plate to the UV rays. Replace the glass plate. Do not turn the UV light towards the students.

Workshop Video



MODERN PHYSICS

7A50.40

QUANTUM EFFECTS

Wave Mechanics

Vibrating Circular Wire

 

The PASCO signal generator drives the PASCO mechanical vibrator. The three node resonance is at 20Hz. Turn up the amplitude after finding the resonance. Other resonances are at 60, 100, 140 Hz. Pin the wire at 180 degrees from the mechanical vibrator to get full numbers of waves.

Workshop Video





MODERN PHYSICS

7B10.10

ATOMIC PHYSICS

Spectra

Student Gratings and Line Sources

 

Pass out the 1"x1" gratings to the students. These have 13,400 lines per inch. Turn on one of the light sources. There is a single filament white light source and six discharge tubes, H, He, Kr, Ar, O2 and Ne. Caution: Turn off the power on the carousel before turning to the next discharge tube.

Workshop Video



MODERN PHYSICS

7D10.10

NUCLEAR PHYSICS

Radioactivity

Geiger Counter and Samples

 

Turn on the counter and place sample under Geiger Tube. Test to see how distance from the sample affects the count. Place objects like: paper, wood, lead and other items between the source and the tube to check their shielding properties.

Workshop Video



MODERN PHYSICS

7D30.60

NUCLEAR PHYSICS

Particle Detectors

Diffusion Cloud Chamber

 

This demo requires advance notice to obtain dry ice. Tracks are most impressive if the students are allowed to view individually. The TV works quite well too.


MODERN PHYSICS

7F10.60

RELATIVITY

Special Relativity

Lorentz Transformation / Time Dilation

 

The Mechanical Universe, chapter 42, and the Hewitt film "Relativistic Time Dilation"