Water
Water exerts forces on any object.
There are two types of force
It’s a force that pushes things up.
That’s why we float in water. You can feel
it when you hold down a floating object
1) Upthrust force
When walking or swimming through
the sea or swimming pool, you feel
that water is pushing you back.
2) Water resistance
A streamlined ship that has a narrow
shape produces low resistance because
the amount of water pushing against it is
relatively small.
2) Air resistance
Air pushes against a moving object. Air
resistance slows down a moving object.
If the object is big in size, the air resistance is
also big and the opposite.
Air resistance can be very useful. The
push of the air on a parachute slows
the fall of the object
Free fall
Hang-gliding Parachutes Gliding

forces Presentation 2

  • 1.
    Water Water exerts forceson any object. There are two types of force
  • 2.
    It’s a forcethat pushes things up. That’s why we float in water. You can feel it when you hold down a floating object 1) Upthrust force
  • 3.
    When walking orswimming through the sea or swimming pool, you feel that water is pushing you back. 2) Water resistance
  • 4.
    A streamlined shipthat has a narrow shape produces low resistance because the amount of water pushing against it is relatively small.
  • 5.
  • 6.
    Air pushes againsta moving object. Air resistance slows down a moving object. If the object is big in size, the air resistance is also big and the opposite.
  • 7.
    Air resistance canbe very useful. The push of the air on a parachute slows the fall of the object
  • 8.