Chapter 4.8, Problem 27E

To determine

Tofind:the streamlines for the flow of water around the inside of right-angle boundary, velocity potential, stream function and velocity.

Answer to Problem 27E

The angle of the elevation to the top of the tower at a point 50 feet from the base of the tower is ${56.31}^0$

Explanation of Solution

Given:

  $\text{AB 75}$ foot high and point C on the level ground at a distance of 50 feet from its base.

Concept used:

The tangent of the angle is given by the ratio of the length of the perpendicular to the base

  $\text{tanθ=}\frac{\text{perpendicular}}{\text{base}}$ it doesn’t depend on hypotenuse.

Calculation:

Consider a cellular telephone tower, $\text{AB 75}$ foot high and point C on the level ground at a distance of 50 feet from its base.

Since the tangent of the angle is given by the ratio of the length of the perpendicular to the base

  $\text{tanC=}\frac{\text{AB}}{\text{BC}}$

Put the values

  $\text{tanC=}\frac{75}{50}$

  ${\text{C=tan}}^{-1}\frac{75}{50}$

  ${\text{C=tan}}^{-1}\left(1.5\right)$

  $\Rightarrow {56.31}^0$

Hence, the angle of the elevation to the top of the tower at a point 50 feet from the base of the tower is ${56.31}^0$