HEIGHT & DISTANCE
`text(ANGLES OF ELEVATION AND DEPRESSION )`
` (i)text( Angle of elevation :)`
Let `P` be an object and `OX` be a horizontal line; an observer at `O` to perceive the object `P` has to elevate his eye from the direction `OX` to the direction `OP.` As such, we define `angleXOP` as the angle of elevation of `P` at `O.`
`(ii)text( Angle of depression:)`
Let `P` be an object and `OX` be a horizontal line; an observer at `O` to perceive the object `P` has to depress his eye from the direction `OX` to the direction `OP.` As such, we define `angleXOP` as the angle of depression of `P` at `O.`
`(iii)text( Angular elevation :)`
If `PM` is perpendicular to `OX,` then the angle `XOP` is also called the altitude or the `text(angular elevation)` of `MP` at `O.`
`(iv)text( Bearing of a point :)`
Let `NS` and `EW` stand for lines in the north-south and east-west directions respectively then the acute angle which the line `OA` makes with `NS` is called the bearing of the point `A` from `O.`
The bearing of `A` may be indicated precisely, by giving the size of the angle and specifying whether it is measured from `ON (` or `OS)` and whether to east (or west). For example, in figure, `OA` is in the direction `30^0` east of north. Thus, the bearing is written as `N \ \ 30^0\ \ E.`
` (i)text( Angle of elevation :)`
Let `P` be an object and `OX` be a horizontal line; an observer at `O` to perceive the object `P` has to elevate his eye from the direction `OX` to the direction `OP.` As such, we define `angleXOP` as the angle of elevation of `P` at `O.`
`(ii)text( Angle of depression:)`
Let `P` be an object and `OX` be a horizontal line; an observer at `O` to perceive the object `P` has to depress his eye from the direction `OX` to the direction `OP.` As such, we define `angleXOP` as the angle of depression of `P` at `O.`
`(iii)text( Angular elevation :)`
If `PM` is perpendicular to `OX,` then the angle `XOP` is also called the altitude or the `text(angular elevation)` of `MP` at `O.`
`(iv)text( Bearing of a point :)`
Let `NS` and `EW` stand for lines in the north-south and east-west directions respectively then the acute angle which the line `OA` makes with `NS` is called the bearing of the point `A` from `O.`
The bearing of `A` may be indicated precisely, by giving the size of the angle and specifying whether it is measured from `ON (` or `OS)` and whether to east (or west). For example, in figure, `OA` is in the direction `30^0` east of north. Thus, the bearing is written as `N \ \ 30^0\ \ E.`
