A sub-marine is 300 m horizontally out from the shore and 90 m beneath the surface of the water. A laser beam is sent from the sub so that it strikes the surface of the water at a point 210 m from the shore. If the beam just strikes the top of a building standing directly at the water's edge, find the height of the building.

Respuesta :

Answer:

the height of the building h= 133.37 m

Explanation:

from the figure,

The angle of incidence of water surface is

[tex]\theta_1= tan^{-1}(\frac{90}{90} )[/tex]

=45°

angle of reflection is

[tex]\theta_2= sin^{-1}(\frac{sin\theta_1n_{water}}{n_{air}} )[/tex]

[tex]\theta_2= sin^{-1}(\frac{sin45°(1.33)}{1} )[/tex]

=70.12°

The height of the building h

[tex]h= \frac{210}{tan70.12\degree}[/tex]

h= 133.37 m

Ver imagen Manetho