1) The arm of a boom crane is 12m long.
Because of the location of the construction site, the angle of inclination
of the boom of the crane has a minimum value of 30° and a maximum of 45°.
Find the vertical displacement of the end of the boom as
a) an exact value
b) an approximate value, to the nearest tenth of a metre.
You're expected to the ratio of the sides of a 30-60 right triangle.
12 * |
* | y1
* 30° |
* - - - - - - - - *
The side opposite the 30°-angle is always one-half the hypotenuse.
Hence: . m.
You should know that sides of a 45-45 right triangle are in the ratio: .
12 * |
* | y2
* 45° |
* - - - - - *
. . . . . . . .