Untitled Flashcard Set

Gravity

A force that pulls objects toward each other.

What is gravity and what does it do?

Gravity is a force that pulls objects toward each other, keeping us, buildings, and objects on Earth.

Earth's gravity

It keeps us, buildings, and objects from floating away.

How does the Sun affect gravity?

The Sun has gravity that pulls planets into orbit.

Air resistance

Slows objects down as they fall.

Rotate

Means to spin.

Axis

An imaginary line through the center of the Earth.

How long does one full rotation of the Earth take?

24 hours (1 day).

Day and night

Happen because of Earth's rotation.

What happens during daytime?

It is daytime when your part of Earth faces the Sun.

What happens during nighttime?

It is nighttime when your part of Earth faces away from the Sun.

Counterclockwise rotation

Earth rotates counterclockwise, causing the Sun to rise in the east and set in the west.

Hemispheres

Half of the Earth.

What are the two main hemispheres called?

Northern & Southern Hemispheres, Eastern & Western Hemispheres.

Horizon

The line where the sky meets the Earth.

What happens at the horizon during sunrise and sunset?

The Sun appears on the horizon.

Standard time zones in the United States

The United States has 6 standard time zones.

What are the main time zones in the US?

Eastern, Central, Mountain, Pacific, Alaska, and Hawaii-Aleutian.

How does time change as you move west in the US?

Time changes by 1 hour as you move west.