Title Physics-full Notes-Form-3 wazaelimu com.pdf ✅

1 Download free notes and past papers from www.wazaelimu.com VECTORS AND SCALARS Quantities are divided into two groups (types). 1. Scalar quantities which have magnitude or size only. Example • Distance • Speed • Mass • Temperature 1. Vector quantities which have both magnitude and direction. Example • Displacement • Velocity • Acceleration • Force etc VECTOR DIAGRAM Since a vector has a magnitude and direction it can be represented by a vector diagram i.e. line which is drawn to scale to represent the magnitude of the vector and an air on it to give its direction i.e. a particle displaced three to the north, this describes a displacement suppose our scale is 1cm well then draw a 3cm line pointing north ward

3 Download free notes and past papers from www.wazaelimu.com Since vectors can be represented by a vector diagram. It is very possible to add two vector or more. A vector which is a sum of a vector is called a resultant vector. It represents a number of vector in magnitude and direction. The effect of the single vector will be the same as that of a number of vectors. Example Let two ropes pull the same body in different directions. The resultant force will be the net effect of the two ropes acting on a body. There are two methods of vector addition 1. The triangle law of vector addition 2. The parallelogram law of vector addition usually we do use the head to tail of the second vector is placed at the head of the 1st vector and the tail of the 3 rd vector at the resultant vector will then be formed by joining the tail of the 1 st vector to the head of the last vector. Always drawing the vector to scale imagining to do and the proper direction. THE TRIANGLE LAW OF VECTOR ADDITION States that " If two vectors in sequence represent the two sides of triangle in magnitude then the third side of the triangle will give the resultant vector" When drawing the head of the first vector should be followed by the tail of the second vector . The third side which represents the resultant vector should be drawn from the tail of one vector and the head of another vector .
4 Download free notes and past papers from www.wazaelimu.com The two vectors should be drawn in such away that, tail of one vector joins the tail of another vector and the resultant vector should be drawn from the common point . Example : 1. Find the resultant force of the two forces 15n and 9n acting on a body making an angle of 600 between them Solution Choose scale