Rewriting trigonometric expressions as rcos(A – α) Student activity Play

Rewriting trigonometric expressions as rsin(A + α) Student activity Play

Reynolds experiment – laminar flow vs. turbulent flow Student activity Play

Rhombuses and squares Student activity Play

Riddles about 3-D shapes Student activity Play

Risk factors for cardiovascular diseases Student activity Play

Risk factors for coronary heart disease Student activity Play

Risk of omission Student activity Play

Rock cycle Student activity Play

Rock transformations Student activity Play

Rockets Student activity Play

Rockets Student activity Play

Rocks and minerals Student activity Play

Roemer's proof Student activity Play

Roentgen spectra of elements – characteristic radiation Student activity Play

Role of bacteria in digestion and in the production of vitamins Student activity Play

Role of bile in lipid digestion Student activity Play

Role of macro-elements absorbed as anions Student activity Play

Role of macro-elements absorbed as cations Student activity Play

Role of plant defence mechanisms in predator/prey balance Student activity Play

Role of the nervous system in homeostasis Student activity Play

Roll a die Student activity Play

Rolling and rotations Student activity Play

Rolling down an inclined plane Student activity Play

Rolling friction Student activity Play

Rolling friction Student activity Play

Root hairs Student activity Play

Root of any order as a power Student activity Play

Root-mean-square current and voltage Student activity Play

Roots Student activity Play