Piezoelectric energy harvesting

What is the piezoelectric effect?

• A material's ability to conduct electricity when heated

• • A material's ability to generate an electric charge in response to applied mechanical stress

  
  

• A material's ability to expand or contract in response to an electric field

• A material's ability to change color when an electric current is applied

Which of the following are common sources of mechanical stress that can be used in piezoelectric energy harvesting?

• Vibrations and pressure changes

• Heat and light

• Radio waves and sound waves

• Magnetic fields and electric fields

What are the primary challenges when designing a piezoelectric energy harvesting system for a wearable device?

• • Identifying a source of mechanical stress and managing power output

  
  

• Making the device waterproof and shockproof

• Making the device visually attractive and lightweight

• Making the device capable of connecting to the internet and updating its software

In the context of a Smart City, where could piezoelectric materials be placed for energy harvesting?

• Underneath roads and in floors to capture energy from traffic and footfall

• • In streetlights to capture energy from light

  
  

• In loudspeakers to capture energy from sound

• In air conditioners to capture energy from heat

Why is power management critical in a piezoelectric energy harvesting system?

• It ensures the device can be used during power cuts

• It ensures that the device can always operate at its maximum power output

• It ensures a steady power supply for the device, storing excess energy when production is high and supplying it when production is low

• It ensures that the device can be remotely monitored and controlled

Which material is not typically used in the construction of piezoelectric devices?

• Quartz

• Lead Zirconate Titanate (PZT)

• Copper

• Polyvinylidene Fluoride (PVDF)

What makes piezoelectric materials suitable for energy harvesting in wearable devices?

• They are robust and inexpensive

• They generate heat when compressed

• They generate an electric charge in response to mechanical stress

• They can store large amounts of energy

What is one potential downside to using piezoelectric materials for energy harvesting?

• They can only harvest energy from sunlight

• They require a constant source of mechanical stress

• They can only harvest energy from high-frequency vibrations

• They generate harmful byproducts

In the context of Smart Cities, how could piezoelectric materials potentially reduce energy costs?

• By replacing all traditional power sources

• By converting mechanical stress into electricity to power small devices or sensors

• By increasing the efficiency of energy transmission

• By storing excess energy for future use

In a piezoelectric energy harvesting system for a wearable device, why is user comfort an important factor to consider?

• Uncomfortable devices are more likely to generate more mechanical stress

• Comfortable devices are more likely to be worn consistently, providing a constant source of mechanical stress

• Comfortable devices are more likely to be worn consistently, providing a constant source of mechanical stress

• • Comfortable devices are more likely to be larger, providing more space for piezoelectric materials