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Forces and Motion

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Forces and Motion Forces and Motion Forces and motion are very important. You may not know but forces are used in everyday life for example: walking, pushing and pulling. Forces cause things to move. Motion is simply a movement but it needs a force to move. There are two types of forces contact force and non-contact force. Contact force is simply two interacting objects touching for example: throwing a ball. Non-contact force is when two objects are not touching are not touching like the moon and the earth ocean Force Firstly, force is just a technical word push or pull. If you push or pull on an object you are applying a force. Secondly, forces make things move or change their motion. There are so many types of forces here are just a few, gravity and magnetism. Different Forces There are two types of forces. Firstly, there is contact force. This is when two interacting objects are physically touching, for example: throwing a ball, when you throw a ball you use friction to push the pall out of your hands. Secondly, the next force is at a distance force. It is when two interacting objects not touching each other like for example: magnets and a paper clip and the moons gravity and the earth ocean. This occurring because of the gravity and magnetism Contact force Contact force is when you are needing to physically touch another object to allow it to move. There are 4 types of contact forces. Firstly normal force is when nothing is occurring, for example: a book on a table. Gravity is pulling down on the book to make it rest. Secondly, the next contact force is applied force. This is when a push or pull is applied to make an object move. Furthermore the third contact force is tension force. This is applied to a cable or wire that are anchored and affects the cable or wire at opposite ends. This causes the force to pull it equally in both directions. At last the fourth and final contact force is spring force. It is a force that is created by a compressed or stretched spring that can push or pull Friction allows you to move around without sliding. The more friction you have the Friction more difficult it is to walk. Friction is also a contact force. It occurs when objects rub against each other it can be helpful. It allows you to walk around without sliding. It also can be destructive. When two objects that rub wear things away. The heavier the object the higher the friction like a toy train and a real train. There are 4 types of friction. Firstly, static friction. Static friction acts on unmoving objects. The word static describes a fixed or stationary object. Once the force is greater than static friction it is no longer applied. Secondly, sliding friction. It occurs between two objects sliding past each other, it also slows things down. This is when bumps on the surface sticks together, they break apart and reform in different places. To overcome sliding friction a force must be constantly applied. Sliding friction is less than static friction {easier to move}. Furthermore, the third type of friction is fluid friction. The force that resists motion when fluid is involved for example: water through a hose. Finally the last type of friction is rolling friction. This is frictional force between rolling objects and a surface, for example: wheels on the car. This has much less friction than there is in sliding friction. It depends on the materials of the wheel, rubber travels less further that steel. Air resistance is a type of friction. It can slow things down and speed things up, like for example: wind blowingInertia ais leaf.when something is moving and has enough momentum Inertia to keep moving. Gravity brings things to a stop. Inetria is not a force. It is the property of all things due to mass. The more mass it has the more inertia it has. It makes things harder or easier to move. Moving objects tend to stay moving {depending on the mass} stationary tend to stay stationary because of inertia. This is a non -contact force because of moons Non-contact force gravity it is pulling the earth ocean, this is how tides form. A non-contact force is a force applied between 2 objects. The first non-contact force is magnetism. Magnets create a magnetic field. It is invisible to the human eye, it only attracts certain types of metal and most metals are not magnetic. Magnets can attract or pull on other magnets. They are magnetic to the North and South Pole, each and every object in the world need to be in the magnetic field to respond to the poles. This occurs because the earth is made out of iron and nichel which is giving magnets a magnetic field. Lastly, gravity. This is a force of attraction being applied between 2 objects. This is occurring because the earth has mass greater than every object, like for example, if you drop an acorn or a piano, it will gain velocity at the same rate. Gravity or the gravitational force is a force of attraction, For example. Earth and the moon Motion Motion is acceleration. It’s how quickly things speed up and slow down. It is the changings of the position or location of things. In order to do this it needs a force. Velocity is like motion. If the direction charges, the speed or velocity changes. Important people Sir Isaac newton was the most Albert Einstein and Sir Isaac Newton were very important person to force and motion Albert Einstein was a well - important people to force and motion. Albert Einstein was the known scientist world’s most famous scientist of all times. He refined some of Newton’s theories through the theory of relativity. Sir Isaac Newton was the greatest English mathematician. Do you believe an apple caused all his theories, he made his 3 laws of motion. His first law is, if something is moving it will keep moving or if the object is at rest it will remain still. His second law of motion is, that when force is acting on an object, it will change its speed or direction or both. His last and final law of motion is, that for every force or action there is always an equal or opposite reaction After all the information on forces and motion it can be understood how forces and motion occurs to everyday life, but most important it makes life as we know it . By Yoel .
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