1.

The shadow of a tower at a time is three times as long as its shadow when the angle of elevation of the Sun is 60^(@). Find the angle of elevation of the Sum at the time of the longer shadow.

Answer»

`60^0`
`30^0`
`45^0`
`15^0`

Solution :Let AB = h be the height of a tower.
Let at Sun's elevation of `60^(@)`, its shadow be x.
some Applications of Trigonometry
Let `theta` be the ANGLE of elevation when its shadow is 3 times the FORMER i.e.,3x.
``In right `DeltaABC`,
`tan60^(@)=h/xrArrsqrt3=h/xrArrh=xsqrt3...(1)`
In right `DeltaABD`,
`tantheta=h/(3x)`
`=(xsqrt3)/(3x)"[from (1)]"`
`=1/sqrt3=tan 30^(@)`
`theta30^(@)`


Discussion

No Comment Found

Related InterviewSolutions