We Only See The Past

The video explains how sound and light travel at different speeds, causing delays in perception. It uses examples like a hammer hitting a pole and lightning to illustrate sound travel. The moon's distance is discussed, showing how light takes time to reach Earth, making us see the moon as it was 1.3 seconds ago. The video also covers galaxies seen by the James Webb Space Telescope, which are billions of light years away, meaning we see them as they were billions of years ago. Finally, it highlights that everything we see is in the past, even objects close to us, due to the time light takes to travel.

Why do we see a hammer hit a pole before we hear the sound?

• Because the pole absorbs sound.

• Because the hammer is closer than the pole.

• Because sound travels faster than light.

• Because light travels faster than sound.

How long does it take for light from the moon to reach Earth?

• 5 seconds

• 1.3 seconds

• 2.5 seconds

• 0.5 seconds

What is the average distance of the moon from Earth in light seconds?

• 1.3 light seconds

• 2.3 light seconds

• 3.0 light seconds

• 0.8 light seconds

How long does it take for light from galaxies 13 billion light years away to reach us?

• 1.3 million years

• 13 billion years

• 13 million years

• 1.3 billion years

How long does it take for light to travel from a phone to your face?

• 1 microsecond

• 1 millisecond

• 1 second

• 1 nanosecond