Radiations originating from atomic and nuclear processes are classified into four types:
charged particulate radiation consisting of
1. heavy charged particles (α)
2. fast electrons (β)
uncharged radiation consisting of
3. electromagnetic...
A point light source will produce seemingly sharp shadows which turn out to be not at all sharp when viewed under magnification. Narrow interference bands are seen within the shadow of a straight edge while more complicated shapes yield...
A telescope (with video output) at the front of the lecture hall is focused on two point light sources at the rear of the hall. Although the light sources are only 1/2 mm apart, they are readily resolved. The Rayleigh limit of resolution can...
Large speaker with signal generator/amplifier destroys a wineglass; stroboscopic illumination shows vibration mode.
Sound waves of the right frequency are used to excite a wineglass in one or two of its normal modes of vibration. Stroboscopic...
A thin wire, moving through the air, is made to vibrate in the audio range at the vortex shedding frequency.
When air flows around an object, there is a range of flow velocities for which a von Karman vortex street is formed. The shedding...
Optical technique that allows us to see small changes in the refractivity of air and other transparent media.
Refraction due to inhomogeneity in air is made visible by our single-mirror schlieren optics setup. The refraction can be caused...
The interactions of the various radiations with matter are unique and determine their penetrability through matter and, consequently, the type and amount of shielding needed for radiation protection. Being electrically neutral, the...
Detection of IR radiation from hair dryer and/or special IR source.
Detection of infra-red radiation by the rotation of a paddle-wheel vane inside a low pressure flask.
A radiometer consists of a partially evacuated flask...
Like visible light, invisible infra-red radiation can be refracted by lenses to produce an image on a screen. Indeed, a slide projector designed for visible light is used as the imaging device; a heat- sensitive screen makes the invisible...
