[2025-26] SPH3U Phys ...

VIDEO LESSON (39:41 min)
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Light is an EM wave.. So are radio waves, and microwaves and gamma rays. They are all parts of the electromagnetic spectrum.

PRODUCING EM RADIATION

Recall Maxwell's Equations tells us that we can produce propagating EM fields from changing electric and magnetic fields.

Take a charge and have it oscillate up and down and a changing electric field will generate a propagating EM wave. 

The faster the charge oscillates the higher the frequency of EM radiation produced.

PRODUCING RADIO WAVES

RECEIVING RADIO WAVES

PRODUCING MICROWAVES

PRODUCING INFRARED RADIATION

PRODUCING INFRARED RADIATION

Infrared radiation is also produced through rotational and vibrational modes in molecules. Different molecules have different resonances due to absorption of wavelengths of light at these resonant frequencies.

 

PRODUCING VISIBLE LIGHT

PRODUCING X-RAYS

PRODUCING GAMMA RAYS 

EXAMPLE DECAY CHAIN

SUMMARY