why do some buildings fall down in earthquake?

What is the natural frequency of a one-meter long pendulum?

• 0.25 hertz

• 0.5 hertz

• 1 hertz

• 2 hertz

What happens when the period of ground motion matches the natural resonance of a building?

• The building undergoes the largest oscillations possible and suffers the greatest damage.

• The building remains unaffected.

• The building undergoes minimal oscillations.

• The building's resonance is canceled out.

What is the resonant frequency of the mass of a low C string?

• 128 hertz

• 500 hertz

• 440 hertz

• 264 hertz

During the 1985 Mexico City earthquake, which buildings suffered the most damage?

• Skyscrapers

• Short old weak stone buildings

• Medium-height buildings with similar natural periods

• All buildings equally

What is resonance?

• The tendency of a system to oscillate with greater amplitude at some frequencies than at others.

• The tendency of a system to remain at rest.

• The process of reducing a system's oscillations.

• The frequency at which a system stops oscillating.

What is the effect of doubling the frequency of a wave on its period?

• The period doubles.

• The period is halved.

• The period quadruples.

• The period remains the same.

How does the ground's resonant frequency affect buildings during an earthquake?

• It increases the building's structural integrity.

• It has no effect.

• It reduces the building's natural frequency.

• It can cause buildings to oscillate more if the frequencies match.

What is the relationship between a building's height and its natural period of resonance?

• All buildings have the same natural period.

• Taller buildings have longer natural periods.

• There is no relationship.

• Taller buildings have shorter natural periods.

What contributes to the resonance disaster of a building?

• The building's color and design.

• The building's location only.

• Prolonged energy input at the system's resonant frequency.

• The building's age.

How can building design prevent resonance disasters?

• By determining the resonant frequency of the ground beneath the building site and modifying the design accordingly.

• By making the buildings as tall as possible.

• By painting the building in light colors.

• By building on soft sediments only.