is a rope or chain with a wheel and axle attached.

.. is a push or pull

Rougher surfaces have ...

What is the name of the forces 1 and 2 ,respectively?

How does friction affect speed?

A flagpole is a fixed pulley

•More the number of pulleys and supporting ropes,

…………..the force required

The rougher the surface, the faster an object will travel over the surface.

Moves an object away from you

If you align two magnets so the south pole of one faces the north pole of the other,

the magnets will move towards each other. This is called ...........

If you line the magnets up so that two of the same poles face each other,

the magnets will move away from each other. This is called ............

Designed to simple and safe work.

pulleys increases the amount of actual force required to lift heavy objects.

a wheel with teeth that meshes with

  another similar gear that is typically larger or smaller

calculate the net force

calculate the net force

calculate the net force

calculate the net force

Gears system interlock in the different direction

A see saw is an example of:

What class lever is a seesaw?

 It does not travel with the load.

Friction is a force that acts in an ___________ direction of movement.

What class lever is a pair of scissors?

What class lever is a pair of pilers?

What class lever is an oar?

What class lever does this picture show?

What class lever does this picture show?

What class lever does this picture show?

Forces in the same directions, we ..... them

What class lever is a nutcracker?

 Look at the shape

 and guess its type

 Look at the shape

 and guess its type

 Look at the shape

 and guess its type

What class lever is a wheelbarrow?

What class lever are tongs?

What class lever is a fishing rod?

What class lever is a pair of tweezers?

You need to lift a heavy statue 30 feet into the air. Which simple machine would be best to use?

For a lever to move, do forces have to be balanced or unbalanced

What does friction produce?

1- The forces shown above are PULLING forces.

2- The forces shown above are OPPOSITE FORCES.

3- . There IS NO motion occur.

Add a lubricant like oil

Friction occurs because the surface of any object is smooth.

If you tried to walk on ice you might slip because there is ....... friction.

This is .............
, measure ..........

A force can change the speed of an object, making it faster or slower

Which one have more hills and valleys ?

and the valleys are deeper?

..... is a pulling force exerted by the Earth

* Force meters with springs made from thicker wire

measure stronger forces.

• * Force meters with springs made from thinner wire

measure weaker forces.

Unit of force is ...

occurs when two things rub against other

Friction occurs because the surface of any object is rough.

Even surfaces that feel smooth are covered with .......................

Friction makes it ........... for things to move.

The amount of friction depends on factors:

Air resistance pushes the cyclist back, opposing the cyclist's force from them pedaling the bicycle and making the bicycle travel more slowly.

This is an unhelpful effect .

moves an object towards you

gravitational pull depends on object's mass

The train is designed to be streamlined to :

which man will land last?

What can friction do?

What is needed for a force to be called a contact force?

Which has more friction and why?

What is the net force shown in the diagram?

... force is pushing in the opposite direction to gravity.

The feather and the hammer hit the surface of the Moon at the different time!

The rougher the surface, the ....... hills and valleys there are and the .......... the friction.

is the push or pull exerted by the magnet

An object with ............. surface area , will experience greater air resistance

Friction can slowdown or stop moving objects

What is the effect of two negatively charged objects coming near each other.

Balanced or Unbalanced force?

Attract or repel?

Plastic is not magnetic.

The force stopping us from floating into space is called gravity.

Some examples of ........ are:

(gravitational , magnetic and electric).

Can you find the metals a magnet can pick up?