M5 social review sept 21-22

If the population density of an earthquake prone area is high, the chances of many people being killed or injured during an earthquake will be high.

• population density

• magnitude of earthquake

During an earthquake, people who live in areas with soft soil tend to be affected more greatly.

• type of soil

• magnitude of earthquake

We cannot feel these.

• magnitude 5

• magnitude 0-1

Rare but would cause unbelievable damage.

• magnitude 9

• magnitude 5

If such infrastructure had been built further away from earthquake prone areas, the number of deaths may have been lower.

• Planning the location of infrastructure

• Strengthening existing Infrastructure

Are conducted regularly in many earthquake-prone countries to educate and familiarize people on what to do in the event of an earthquake.

• Designing new infrastructure

• Drills

To reduce the damage that may be caused in an earthquake, steel bars are placed across an existing bridge and then covered with concrete to strengthen it.

• Strengthening existing Infrastructure

• Planning the location of infrastructure

It measures and locates earthquakes and other ground motions.

• seismometer

• drills

The first seismometer was invented in _______.

• 135 BC

• 132 BC

Who invented the first seismometer?

• Zhang Heng

• Cheng Sue