P waves travel at about 500 km/hour. How long would they take to travel to the opposite side of the Earth from the spot of an earthquake?

 

earthquake
Actually between 40 minutes to an hour. Roughly speaking.
P-waves travel at different speeds through different densities of rock, from around 2 km a second through the Earth’s crust to about 8 km a second through the earth’s mantle.
Just roughly averaging it lets take the speed of 4 km a second. That is 14,400 km an hour!
Earth’s diameter is 12,756 km so it is just under an hour.

Earthquake

An earthquake (also known as a quake, tremor or temblor) is the result of a sudden release of energy in the Earth’s crust that creates …