Forces Lesson

Forces

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​​How do objects affect other objects?

​​Position and Motion

• An object’s position refers to its place or location.  ​

• ​Motion is when an object’s position changes compared to the objects it is around. 

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Example: If a bird flies away from a tree, the bird’s position changed in comparison to the tree.

​Force

​​​• A Force cause an object’s motion to change through pushes or pulls.

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​• If you push an object, you are using a force to move the object away.  

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• If you pull an object, you are using a force to move the object closer.

​Force

​Forces can…

• Change the motion of an object

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• Make an object start moving

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• Change the direction of an object

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• Change the speed of an object

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• Make an object stop moving

Multiple Choice

What is an object' position?

• its place or location

• its size

• its movement

• its change in location

Multiple Choice

What is motion? 

• how fast an object moves

• an objects location or place

• when an object’s position changes compared to the objects it is around

• when an object changes in size

Multiple Choice

What is a force? 

• Something that causes an object to change its apperance. 

• Something that moves.

• Something that causes an object’s motion to change through pushes or pulls.

• Something that does not move. 

There are many different types of forces.

Lets take a look at some types of forces and how they affect objects. ​

​Friction

Friction is a force that will stop or slow down the motion between two surfaces or objects that are touching one another.

 

• For example, if you are pushing a box across the floor and then stop pushing, the box will not continue sliding because of friction between the box and the floor. If the floor was slippery and the box kept sliding, that means there was no friction between the box and the floor.

​Friction

• Rough surfaces such as carpet or cement have more friction.

• Smooth surfaces such as hardwood floors or tile have less friction.

• In turn, it is harder to move a box on a carpeted floor because there is more friction between the box and the carpet.​It is easier to move a box on a hardwood floor because there is less friction between the box and the hardwoods.

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​Friction is useful because…

• Friction helps us walk without slipping and sliding everywhere

• Friction helps us hold objects

• Friction helps us ride a bike

​Gravity

• ​​The downward attraction of gravity is called the weight of an object. The heavier the object, the faster it will be pulled down.

• ​If you hold up your pencil and let it fall, it will drop to the floor. This an example of gravity pulling an object down.

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​Gravity is a natural force that pulls all things on Earth down towards its center.

Magnetism

​Magnetism is a natural force that pushes and pulls certain metals.

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​Magnets have two sides called poles. There is a north pole and south pole.

• If you put the north and south poles together, they attract one another, which means they are pulled together.

• ​If you try to put the north end close to the north end of another magnet, or the south pole with the south pole, you will feel the magnets push apart. This is called repulsion.

​Static Electricity

​​Static Electricity is the build up of electricity on an object. That build up results in a positive or negative charge that will attract or repel an object.

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• R​ubbing an object will build up a big electrical charge, The charge can be either positive or negative. Similar to magnets, opposite charges attract and like charges repel.

• ​When you slide down a slide, the friction causes a positive charge on your hairs. Because each hair has a positive charge, they push away from each other. That is why your hair sometimes sticks up when you go down a slide.

Multiple Choice

What is friction? 

• a force that does not affect an objects motion

• a force that cause an object to fall to the ground

• a force that will speed up the motion between 2 surfaces or objects that are touching one another 

• a force that will stop or slow down the motion between 2 surfaces or objects that are touching one another

Multiple Choice

What is gravity?

• a natural force that pulls all things on Earth down towards its center.

• a force that stops or slows down the motion of an object

• a natural force that speeds up the motion of an object

• a force that allows an object to float in mid-air

Multiple Choice

What is magnetism?

• a natural force that stops the motion of certain metals

• a natural force that pushes and pulls certain metals

• a natural force that pulls down an object

• a natural force that changes the size of an object

Multiple Choice

What is static electricity?

• a force that speeds up the motion of an object

• the build up of motion

• the build up of electricity on an object

• a force that stops the motion of an object