Aim: What is Earth’s daily motion? DO NOW: 1. How many hours are in one day? 2. How many degrees is a full circle? 3. How many degrees does Earth spin.

Aim: What is Earth’s daily motion?DO NOW:1. How many hours are in one day?2. How many degrees is a full

circle?3. How many degrees does Earth

spin in one hour?4. What do hachure lines represent

on a topographic map?5. How can you tell there is a river

valley on a contour map?

How does Earth move?

•Earth spins like a top as it travels in outer space. •This spinning is called ROTATION.•We say it spins about it’s axis.

What is Earth’s rotational speed?Speed changes with latitude.

The Equator spins fastest because its wider.

The Poles; North and South, spin slowest because they are smaller.

WHICH WAY DOES EARTH SPIN?

•Earth rotates in a compass direction of west to east or easterly.

•Clock direction of counterclockwise.

How can we remember? Use the right hand rule!

Hold out your right hand in a thumbs up position: your fingers will be pointing counter-clock-wise.

Why do celestial objects; such as stars, move in our sky?

Earth’s rotation creates the illusion that many celestial objects are moving.

WHAT ARE CELESTIAL OBJECTS?

•Anything outside Earth’s atmosphere!•Ex: Stars, planets, comets, meteors, etc.

What other effects does Earth’s rotational motion cause?

•1. The daily rising of the Sun in the east and setting in the west.

•2. The Sun’s apparent motion of 15o/hr from the east to the west.

How many degrees will the Sun appear to move in 3 hours?

•3 hours x 150 •450

What does the sun’s motion cause us?

3. The cyclic change from day to night.

4. EARTH’S DAILY ROTATION CAUSES THE APPARENT MOTION

OF THE STARS.PROOF: CIRCULAR STAR TRAILS.

Please observe this demonstration.

• 5. The Coriolis Effect; deflection or bending of winds. • a) To the right in the Northern Hemisphere • b) To the left in the Southern Hemisphere.

WHY DO PLANES TRAVEL FASTER IN ONE DIRECTION VERSUS THE OTHER?6. The Jet Stream A strong planetary wind belt found in the upper atmosphere.

Their direction:Easterly or from west to east.

What is the #1 piece of evidence that Earth Rotates?

• The best evidence is credited to Jean Foucault and his pendulum experiment.

• Foucault’s pendulum is a model still used today to demonstrate that Earth spins once on its axis over the course of a 24 hour period.

• Foucault Pendulum

• If the pendulum is swung in a north to south direction, the pegs at 12 and 6 on the clock would be knocked down.

• As Earth rotates counterclockwise, the pendulum stays in a North South direction, but the face of the clock moves beneath it.

•Which pegs would be knocked over next?

• 1 & 7.

Answer these please…

• List 2 of Earths motions

• Rotation (on axis) & Revolution (around Sun)

• How many degrees does Earth move in 1 hr?

• 15

• Which compass direction does Earth spin?

• Easterly or west to east

• Which way do winds deflect in the northern hemisphere?

• To the right

• What is the #1 pc of evidence that Earth rotates?

• Foucault pendulum!