General Relativity: Curved Spacetime and Its Tests · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Gravity as curved spacetime

Science · Astronomy & Astrophysics · ages 21-22
Name ______________________   Date ____________

  1. In general relativity, what is gravity?

    • A rope pulling through space
    • The curvature of spacetime
    • A magnet inside planets

  2. What does the equivalence principle say about a small sealed room?

    • Gravity and acceleration feel identical inside it
    • Gravity vanishes inside it
    • Only light can enter it

  3. Stronger gravity makes clocks tick more slowly.

    Circle one:   True   False

  4. Which observation tests curved spacetime at Mercury?

    • Its orbit creeps forward more than Newton predicts
    • Its surface glows brighter each year
    • Its moons wobble visibly

  5. Why does light bend near the Sun?

    • The Sun's heat pushes the beam aside
    • The beam follows the straightest path through curved spacetime
    • Mirrors near the Sun reflect it

  6. Why do navigation satellites need a relativistic correction?

    • Their radios cannot reach the ground
    • Their orbits never change
    • Their clocks tick differently than ground clocks

  7. Light climbing away from a star reddens. What does that show?

    • The star is cooling down rapidly
    • Dust paints the beam red
    • Gravity stretches the light as it climbs out

  8. A student explains Mercury with a hidden extra planet. What is the better account?

    • A stronger solar wind pushes Mercury along
    • Curved spacetime near the Sun shifts the orbit
    • Mercury's own spin drags it forward
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Answer key

For grown-ups. Fold this page away before handing over the rest.

Gravity as curved spacetime W1-mt_-rZZxZwU2L-s1

  1. The curvature of spacetime · Mass shapes spacetime, and shaped spacetime guides motion.
  2. Gravity and acceleration feel identical inside it · No experiment inside can tell free fall from deep space.
  3. True · Time itself runs slower where gravity is stronger.
  4. Its orbit creeps forward more than Newton predicts · The extra shift matches the curve near the Sun exactly.
  5. The beam follows the straightest path through curved spacetime · Curved paths are the straightest routes available there.
  6. Their clocks tick differently than ground clocks · Different gravity means different clock rates, which shifts positions.
  7. Gravity stretches the light as it climbs out · Escaping gravity costs the light energy, reddening it.
  8. Curved spacetime near the Sun shifts the orbit · Curvature predicts the extra creep with no new planet needed.
Worksheet · LightMySky