A force is push or pull on a object.
A force changes the motion of a moving object.
A force can be strong or weak and is always has direction.
The earth is a planet that goes around the sun in a circular orbit
This speed of motion doesn't change,but direction of motion does.
The earth has a layer of gas above its surface which helps to support life
Atoms are the building blacs of matter.
At the center of an atom is its nucleus,which has a positive electric charge
Outside the nucleus are electron which have negative charge
Asteroids that pass closed to the Earth are called near-earth objects.
Without an atmosphere,there would be no life on Earth.
If they colide with Earth they could cause an extinction event.
A rectangle is a two dimensional figure with 4 sides.
The two lines on the left intersect each other at a right angle,which is 90 degrees.
The two lines on the right are parallel which means they never cross.
The earth is a planet that goes around the sun in a circular orbit.
All points on the surface of a sphere are equidistant from its center
The opposite sides of a rectangle are equal and parallel,which means they never cross.
The area of a rectangle is the length times the width
A force can increase or decrease the speed of an object,and it can change the direction of motion
