Use mathematical representations to describe a simple model for waves that includes how the amplitude of a wave is related to the energy in a wave.

  1. Tech

    Ground-thumping cheers help scientists

    Eager to test new sensors before the next ‘big one,’ earthquake scientists make use of a predictable source of ground-shaking: football fans.

  2. Tech

    Making cents of sounds

    Some people give up when a vending machine rejects their money. But one student decided to turn his frustration into inspiration. Through research, he showed how to identify coins by the sounds they make.

  3. Tech

    Explainer: What are lidar, radar and sonar?

    Radar, sonar and lidar and are three similar technologies. Each relies on the echoing of waves — radio, sound or light waves — to detect objects.

  4. Tech

    Laser vision reveals hidden worlds

    From discovering ancient ruins to forecasting climate change, the laser mapping technology called lidar is changing many fields of science.

  5. Earth

    Nepal earthquake offers hints of worse to come

    The magnitude 7.8 earthquake that crumbled much of Nepal’s capital city could be overshadowed by larger future earthquakes along the Himalayas, scientists say.

  6. Space

    Radio telescope picks up signals from intelligent life

    Astronomers tracked down the source of perytons, mysterious radio bursts. They had at first seemed to emanate from Earth’s atmosphere. Probing now suggests the life forms responsible had a penchant for leftovers.

  7. Earth

    The quake that shook up geology

    North America’s biggest earthquake struck 50 years ago. Here’s what science has learned about Earth since the 1964 Great Alaskan Earthquake.

  8. Earth

    Explainer: Telling a tsunami from a seiche

    Waves that hit coastlines with ferocious power, tsunamis are one of the planet’s most devastating forces of nature. And seiches: They’re tsunamis little, but still potentially deadly, cousins.

  9. Space

    How the outer sun gets so hot