Physical Quantities and Units As/A Level Physics @ferrytanoto
Physical Quantity Is a feature of something which can be measured, e.g. length, weight, or time of fall. Every physical quantity has a numerical value (magnitude) and a unit, e.g. 25 m is the physical quantity of length; 25 is the magnitude and metre is the unit.
Vector Representation One way to represent a vector is by means of an arrow. The directionof the arrow is the directionof the vector quantity. The lengthof the arrow, drawn to scale, represents its magnitude.
Addition of Vectors The combined effect of two (or more) vectors is called the resultant. Coplanar (all in the same plane) vectors may be added (or subtracted) using a vector diagram. The resultant may be found using a scale drawing of the vector diagram of by calculation.
Resolution of Vectors A single vector may be divided into two separate components. The dividing of a vector into components is known as the resolution of the vector. In general, a vector is resolved into two components at right-angles to each other.