What is the difference between a scalar and a vector b How d

What is the difference between a scalar and a vector? b) How do we know if two vectors are perpendicular? An object located at the origin in a three-dimensional coordinate system is held in equilibrium by four forces. One has magnitude 7 lb and points in the direction of the positive x-axis, so it is represented by the vector 7i. The second has magnitude 24 lb and points in the direction of the positive y-axis. The third has magnitude 25 lb and points in the direction of the negative z-axis. a) Use the fact that the four forces are in equilibrium (that is there sum is 0) to find the fourth force. Express it in terms of the unit vectors i, j, k. b) What is the magnitude of the fourth force?

Solution

1) a) A scalar quantity is a one dimensional measurement of a quantity, like temperature, or weight. A vector has more than one number associated with it. A simple example is velocity. It has a magnitude, called speed, as well as a direction, like North or Southwest or 10 degrees west of North

b) If two vectors are perpendicular then there scalar product will be zero.