Displacement and satellite motion

R.E. Tremblay

all rights reserved

If air friction can be neglected, all

objects in free-fall, near the

Earth’s surface, accelerate down

at approximately 10 m/s/s.

An object with an initial vertical

velocity of 0 m/s will fall 5 meters

in the first second of free-fall.

The crate lands toward the

rear of the car

Note that the plane is moving

from right to left

Front of car

Path of

crate

crate

Satellite motion

8 km/s

Drops 5 meters in 1 second

Escape velocity

• A projectile, moving away from the

Earth at 11.2 km/s, will escape the

Earth’s pull of gravity.

Objects in your car are moving

with the same velocity as the

car.

If you toss an apple out the

window, it will be moving

forward with the same speed

as the car.

Although wind friction will slow the

object down, it will still be moving

forward until it hits the ground.

Why don’t communication

satellites that appear to hover

‘motionless’ above the Earth,

crash?

Satellites in geosyncronous

orbits, are actually moving very

fast. They take 24 hours to

orbit the Earth.

The Moon is a satellite of the

Earth.

The ball will fall from a straight line path

the same distance that the object falls.

• 5 meters in 1 second, 20 meters in

2 seconds…..

Straight line path

There is no permanent dark

side of the moon

• X marks the side that

always faces the earth.

North pole

x

x

x

x