How do objects move17 18

1. How do objects move?

2. - It is the change in the position (Location)
Motion

3. Types of motion
Up and down
motion
Ex. See saw
Straight line
motion
Round and
round motion
Ex. Merry go
round
Zigzag
motion
Back and forth
motion
Ex. Swing

4. How can we measure motion?
- Motion can be fast or low.
Distance
-It is how far an object is from one position to
another.
- Measured by: Ruler & Measuring tape
- Units: Cm, meters & kilometers.

5. Time
- Units: seconds, minutes , hours, days, years.
Speed
-It is the distance an object moves in a certain time.
Speed = Distance/Time

6. Things that affect motion of an object
1- The strength of the force:
Toss ball gently it will be near
Toss ball hard it will be far

7. Any type of push & pull
Force

8. - Pushing the table to the right.
- Pulling the drawer out.
- Pushing the stroller to the left.
2- The direction of the force:

9. - It is the amount of material in an object.
Small mass is easy to move
Big mass is harder to move
{It is easier to push an empty shopping cart
than to push a full one}
3- The mass of the object:

10. - It is the kind of force that stops or slows things
down.
{It prevents us from slipping or falling down}
- It is caused when two objects rub together.
Friction

11. • Friction always works in the direction
opposite from the direction the object is
moving, or trying to move. It always slows
a moving object down.
Moving
Friction
Friction

12. Examples
1) Friction between the tires of a car & the
road.
2) Friction between the bottom of your
sneakers & the ground.

13. 3) Friction between the brakes of the bicycle &
the bicycle wheels.
4) Friction between the train
Wheels & rails

14. • The amount of friction depends on the materials from
which the two surfaces are made. The rougher the surface,
the more friction is produced. For example, you would have
to push a book harder to get it moving on a carpet than you
would on a wooden floor. This is because there is more
friction between the carpet and the book than there is
between the wood and the book.
Friction

16. Increasing / Decreasing friction
• Ice & water make surfaces slippery, this
decrease the friction.
{This why skaters can slide easily & smoothly}

17. • Tires of cars have rough surfaces to increase
the friction between the road & the car
preventing cars from slipping on an inclined
plane.

18. • Lubricating “putting oil” to bicycles decrease
friction & makes bicycles move faster.
• Lubricating doors decrease friction making
doors easy to open & close