Reflection of plane waves Student activity Play

Reflection of plane waves Animation Play

Refraction Class activity Play

Relationship between the force of friction and the roughness of a surface Animation Play

Relationship between the force of friction and the surface area Animation Play

Reversible and irreversible reactions Student activity Play

Reversible processes Whiteboard exercise Play

Role of growth hormone Slideshow Play

Sample preparation Animation Play

Satellite telephones Student activity Play

Section through intestinal epithelium tissue Illustration Play

Sections of a cube Student activity Play

Sections of a cube Whiteboard exercise Play

Seed germination and development of vegetative organs Student activity Play

Seismic waves Slideshow Play

Seismic waves Student activity Play

Shooting stars Animation Play

Silver halides in photography Student activity Play

Simple plant tissues Illustration Play

Skeletal muscle Slideshow Play

Solid substances as catalysts in reactions in the gaseous phase Animation Play

Special cells in plants Slideshow Play

Specificity of hormone activity Student activity Play

Specificity of hormone activity Whiteboard exercise Play

Speed of light in transparent materials Illustration Play