Earthquakes- Measurement Quiz

What instrument is used to detect, measure, and record seismic waves?

• Seismograph

• Thermometer

• Anemometer

• Barometer

Answer explanation

A seismograph is the instrument specifically designed to detect, measure, and record seismic waves generated by earthquakes or other ground movements, making it the correct choice for this question.

Which type of seismic wave is the slowest and travels close to the Earth's surface?

• Body Waves

• Surface Waves

• S Waves

• P Waves

Answer explanation

Surface waves are the slowest seismic waves and travel along the Earth's surface, causing the most damage during an earthquake. In contrast, body waves (P and S waves) travel through the Earth's interior and are faster.

What scale is used to measure the magnitude of an earthquake?

• Mercalli Scale

• Richter Scale

• Fujita Scale

• Beaufort Scale

Answer explanation

The Richter Scale is specifically designed to measure the magnitude of earthquakes based on seismic wave data. The Mercalli Scale measures intensity, the Fujita Scale rates tornado damage, and the Beaufort Scale assesses wind strength.

Which type of wave compresses and expands as it travels through the mantle?

• Rayleigh Waves

• Surface Waves

• S Waves

• P Waves

Answer explanation

P Waves, or primary waves, are compressional waves that travel through the mantle by alternately compressing and expanding the material. This characteristic distinguishes them from S Waves and surface waves.

What does the Mercalli Scale measure?

• Depth of the earthquake's focus

• Speed of seismic waves

• Damage caused by an earthquake

• Magnitude of an earthquake

Answer explanation

The Mercalli Scale measures the damage caused by an earthquake, assessing its effects on people, buildings, and the Earth's surface, rather than its magnitude or the speed of seismic waves.

How many times greater is a magnitude 6 earthquake compared to a magnitude 5 on the Richter Scale?

• 10 times

• 20 times

• 5 times

• 2 times

Answer explanation

A magnitude 6 earthquake is 10 times greater than a magnitude 5 on the Richter Scale. The scale is logarithmic, meaning each whole number increase represents a tenfold increase in measured amplitude.

Which of the following is NOT a method for predicting earthquakes?

• Foreshocks

• Weather patterns

• Seismic gaps

• Animal behavior

Answer explanation

Weather patterns are not a recognized method for predicting earthquakes. In contrast, foreshocks, seismic gaps, and animal behavior have been studied for their potential to indicate seismic activity.

What is the primary difference between magnitude and intensity?

• Magnitude is measured by the Mercalli Scale; intensity by the Richter Scale

• Magnitude measures energy released; intensity measures effects

• Magnitude measures effects; intensity measures energy released

• Magnitude is subjective; intensity is objective

Answer explanation

The correct choice is that magnitude measures energy released during an earthquake, while intensity measures the effects and damage caused by the earthquake at different locations.

Which type of seismic wave arrives first at a seismograph?

• Love Waves

• S Waves

• Surface Waves

• P Waves

Answer explanation

P Waves, or primary waves, are the fastest seismic waves and arrive first at a seismograph. They are compressional waves that travel through solids, liquids, and gases, making them the first to be detected during an earthquake.

What is the main characteristic of S (Secondary) Waves?

• They are the fastest waves

• They travel through liquids

• They compress and expand

• They vibrate at right angles

Answer explanation

S (Secondary) Waves are characterized by their motion, which vibrates at right angles to the direction of wave travel. This distinguishes them from P (Primary) Waves, which compress and expand.