# Suppose that p- and s-waves traveled in straight lines through the Earth (in fact, they don’t,…

Suppose that p- and s-waves traveled in straight lines through

the Earth (in fact, they don’t, but we will make this approximation

for this problem). Also suppose that the angular distance from the

epicenter (location of the earthquake) on the Earth’s spherical

surface to the location on the surface beyond which no s-waves can

be observed from an earthquake (the angle between the earthquake

epicenter and the s shadow zone) is 120 degrees (i.e., the two

points are located 1/3 of the Earth’s circumference from each

other). What is the radius of the liquid outer core of the Earth

divided by the radius of the Earth (i.e., what is their ratio)?

Hint: draw a diagram and use trigonometry to find the answer. Do

not give the answer in km or miles, but as a fraction of the

Earth’s radius.