Sixth-form physics and chemistry

First-year sixth-form physics and chemistry is where secondary-school knowledge stops being enough. The topics sound familiar — motion, forces, reactions — but now everything is calculated: you read a velocity-time graph and get the acceleration and distance from it, split weight into components on an incline, or work out how many grams of product a reaction gives when one reactant runs out before the other.

Nearly all exam mistakes are in the setting up, not the arithmetic: using sine instead of cosine, putting the temperature in degrees Celsius into PV = nRT, confusing the limiting reactant with the one with fewer moles, or distance travelled with displacement. The questions on this page use exactly those mistakes as options, and every explanation says where the right number comes from and where the wrong ones do.