1. The document describes an experiment that investigated how the type of surface affects the movement of an object. It found that rougher surfaces like sandpaper produced more friction than smooth surfaces or surfaces with rollers. 2. It then discusses the four main types of friction: static, sliding, rolling, and fluid friction. Static friction acts on non-moving objects, while sliding friction occurs when surfaces slide against each other. Rolling friction is easier to overcome than sliding friction. Fluid friction happens when a solid object moves through a fluid. 3. Understanding friction is important for activities like cycling, dancing, and engineering machines with moving parts.

1. 3rd Quarter: Week 1 Day 1
SCIENCE 6
Grade VI- Carnation
B.T. LAZARO MEMORIAL
SCHOOL

2. Study the pictures. Identify the word
that could describe the picture.

3. Friction

4. Activity 3.1: Comparing Movements
of Objects on Differenet Surfaces
 Problem: How does the kind of surface affect
the movement of an object?
 Materials:
block of wood spring scale hook
sand paper baby powder rods
tape

5. Procedure:
1. Attach a piece of sand paper on one side of the
block of wood.
2. Hook a spring scale to the block of wood. Place
the wood on the table. (The sandpaper should
meet the surface of the table.)
3. Using a steady force, use the spring scale to
pull the wood across the table at a steady
speed. Record the force applied to pull the
block of wood across the table.

6. 4. Remove the sandpaper from the block of
wood. Sprinkle a small amount of powder
on the table. Repeat Step 3.
5. Place several rods on the table. Place the
block of wood on top of the rods. Then,
repeat Step 3.

7. Observation
Kinds of
Surface
Force Exerted (N)
Trial 1 Trial 2 Trial 3 Trial 4
Smooth
surface
Rough
surfaces
Surface with
rollers

8. What have you found out?
 1. What affects the motion of the block of
wood? __________________
 2. What kind of friction is shown when you
let the block of wood with sandpaper slide
on the surface of the table?
______________________________
 3. What kind of friction is shown when you
let the block of wood roll on rods?
______________________________

9. What have you found out?
 4. Under what kind of condition was the
frictional force smallest? _____________
 5. How do rellers help in decreasing the
amount of force needed to pull the block of
wood? ___________________________
_________________________________

10. Conclusion
 What have I learned in the activity?
 __________________________________
__________________________________
__________________________________
__________________________________
__________________________________
__________________________________

11. 3rd Quarter: Week 1 Day 2
SCIENCE 6
Charlito B. Arce
Conchu Elementary School
Trece Martires City, Cavite 4109

12. Kinds of
Friction

13.  What happens when you jump on a
slide?
 You can predict that you will slide
down.
 Now think about what happens at the
bottom of the hill.
 Will you keep sliding?
 You can predict that you will slow
down and stop.

14. Let’s recall!
1. What was our activity yesterday all
about?
2. Can you give an example where
friction occurs.

15.  The force that two surfaces exert on
each other when they rub against each
other is called friction.
Friction

16. The Causes of Friction
 In general, smooth surfaces produce
less friction than rough surfaces.
 The strength of the force of friction
depends on two factors:
How hard the surfaces push
together
The types of surfaces involved

17.  Friction also increases if surfaces push
hard against each other.
 If you rub your hands together
forcefully, there is more friction than if
you rub your hands together lightly.

18.  Friction acts in a direction opposite to
the direction of the object’s motion.
 Without friction, a moving object might
not stop until it strikes another object.

19. Static Friction
 Four types of friction are shown in Figure 6. The friction
that acts on objects that are not moving is called static
friction.
 Because of static friction, you must use extra force to
start the motion of stationary objects.
 For example, think about what happens when you try to
push a heavy desk across a floor.
 If you push on the desk with a force less than the force
of static friction between the desk and the floor, the desk
will not move.
 To make the desk move, you must exert a force greater
than the force of static friction.
 Once the desk is moving, there is no longer any static
friction.
 However, there is another type of friction—sliding
friction.

20. Sliding Friction
 Sliding friction occurs when two solid surfaces
slide over each other.
 Sliding friction can be useful.
 For example, you can spread sand on an icy
path to improve your footing.
 Ballet dancers apply a sticky powder to the soles
of their ballet slippers so they won’t slip on the
dance floor.
 And when you stop a bicycle with hand brakes,
rubber pads slide against the tire surfaces,
causing the wheels to slow and eventually stop.
 On the other hand, sliding friction is a problem if
you fall off your bike and skin your knee!

21. Rolling Friction
 When an object rolls across a surface,
rolling friction occurs.
 Rolling friction is easier to overcome than
sliding friction for similar materials.
 This type of friction is important to
engineers who design certain products.
 For example, skates, skateboards, and
bicycles need wheels that move freely.

22.  So engineers use ball bearings to reduce
the friction between the wheels and the
rest of the product.
 These ball bearings are small, smooth
steel balls that reduce friction by rolling
between moving parts.

23. Fluid Friction
 Fluids, such as water, oil, or air, are
materials that flow easily.
 Fluid friction occurs when a solid
object moves through a fluid.
 Like rolling friction, fluid friction is
easier to overcome than sliding
friction.

24.  This is why the parts of machines that
must slide over each other are often
bathed in oil or lubricants.
 In this way, the solid parts move through
the fluid instead of sliding against each
other.
 When you ride a bike, fluid friction occurs
between you and the air.
 Cyclists often wear streamlined helmets
and specially designed clothing to reduce
fluid friction.