Mammoth Memory

Refraction mnemonic

If a ray of light passes across the boundary from a material in which it travels fast into a material in which it travels slower, then the light ray will bend towards the normal.

FAST TO SLOW = TOWARDS THE NORMAL

If a ray of light passes across the boundary from a material in which it travels slowly into a material in which it travels faster, then the light ray will bend away from the normal.

SLOW TO FAST = AWAY FROM THE NORMAL

The way to remember this is to remember:

Fast Sofa Mnemonic

Think fast sofa.

Fast sofa image

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