Rectangular Refraction Acrylic Block, 115 x 65 x 18mm Subcategory_Spectroscopy Adjustable iris from closed to

Adjustable iris from closed to a 30mm maximum aperture inside a 3-inch black metal body

Hand-driven Newton's color disc that spins seven painted segments fast enough to merge into apparent white through persistence-of-vision and additive color mixing

5% accuracy on a 60mm scale

and PVC for comparative density and material-properties exploration

and ice-pail induction

Rectangular Refraction Acrylic Block, 115 x 65 x 18mm Subcategory_Spectroscopy Adjustable iris from closed toMid size 115 by 65 by 18mm acrylic rectangular refraction block, the lightweight lab safe body matching glass block teaching geometry without the mass or fragility.