Simple machines
Simple Machines
Simple machines are basic mechanical devices for applying force. Most machines are made up of one or more of these machines. There are 6 different types of simple machines. These include:
- Pulleys
- Levers
- Wheel and Axels
- Screws
- Inclined planes
- Wedge
Pulleys
A pulley is a simple machine that makes it easier to lift an object. Pulleys are wheels with a groove along their edge. The wheel is used to change the size or direction of the force used. The simplest pulley system is made of one pulley. This system only changes the direction of the applied force. As a person pulls down on the rope, the weight on the other side of the rope pulls up. The more pulleys that are used, the easier it becomes to lift the load. All pulleys consist of rope wrapped around one or more wheels. Some examples of its use in our everyday activities include: the pulleys that help raise flags, the pulleys inside the construction cranes and the pulleys in the blinds of our homes.
Levers
A lever is a solid rod or bar that is supported at a turning point, called the fulcrum. The force used to operate the lever is known as the effort, and the force that overcomes it is called the load. Levers allow us to lift much heavier objects than normal. Applying a small force at one end can get a larger force out of he other end. The position of the fulcrum can be changed depending on what you want the lever to do. Levers are grouped into 3 different classes. In class 1 levers the fulcrum is in the middle. The lifting force is applied at one end of the lever and is magnified at the other. In class 2 levers the lifting force is magnified from your arms to pick up heavy loads and the fulcrum is at one end of the lever and the lifting force is on the other end creating a magnified force to lift the load in the middle of the lever. In a class 3 lever the force is applied to the middle of the lever. The fulcrum is at one end of the lever and the load is at the other end. An everyday example of this type of lever is a pair of tweezers. Other everyday examples of levers include a crowbar, a see-saw and a wheelbarrow.
Simple machines are basic mechanical devices for applying force. Most machines are made up of one or more of these machines. There are 6 different types of simple machines. These include:
- Pulleys
- Levers
- Wheel and Axels
- Screws
- Inclined planes
- Wedge
Pulleys
A pulley is a simple machine that makes it easier to lift an object. Pulleys are wheels with a groove along their edge. The wheel is used to change the size or direction of the force used. The simplest pulley system is made of one pulley. This system only changes the direction of the applied force. As a person pulls down on the rope, the weight on the other side of the rope pulls up. The more pulleys that are used, the easier it becomes to lift the load. All pulleys consist of rope wrapped around one or more wheels. Some examples of its use in our everyday activities include: the pulleys that help raise flags, the pulleys inside the construction cranes and the pulleys in the blinds of our homes.
Levers
A lever is a solid rod or bar that is supported at a turning point, called the fulcrum. The force used to operate the lever is known as the effort, and the force that overcomes it is called the load. Levers allow us to lift much heavier objects than normal. Applying a small force at one end can get a larger force out of he other end. The position of the fulcrum can be changed depending on what you want the lever to do. Levers are grouped into 3 different classes. In class 1 levers the fulcrum is in the middle. The lifting force is applied at one end of the lever and is magnified at the other. In class 2 levers the lifting force is magnified from your arms to pick up heavy loads and the fulcrum is at one end of the lever and the lifting force is on the other end creating a magnified force to lift the load in the middle of the lever. In a class 3 lever the force is applied to the middle of the lever. The fulcrum is at one end of the lever and the load is at the other end. An everyday example of this type of lever is a pair of tweezers. Other everyday examples of levers include a crowbar, a see-saw and a wheelbarrow.
Wheel and Axel
A wheel is a type of lever that turns in circles about its centre - the fulcrum. An axle usually links the lever and the wheel. A wheel and axle comprises of a wheel, a flat surface with its edges rounded off and an axle. Wheel and axles are sometimes used as a force magnifier or a distance magnifier. It is used as a force magnifier when the outside edge of the wheel moves a larger distance than the axle which amplifies the force. It can also be used as a distance magnifier. When you pedal a bike, you apply force to the pedals. This force causes the larger wheels to turn. The distance the wheel travels is much further than the distance the pedal travels. the distance has been magnified. Wheel and axles are usually used to transport things easier. Some examples of wheel and axles include: a doorknob, a car wheels and a Ferris wheel.
Screws
A screw is a special type of inclined plane. It has a ridge, called a thread, cut around it in the form of a spiral. Screw penetrate materials such as wood or cork by using the turning effect of a force. The effort needed to turn a screw into an object is much less than the effort needed to hammer the screw into the same object. Screws are used to help hold things in place. Some examples of screws include: jar lids, drills and bolts.
Inclined Planes
Inclined planes, also known as ramps, are used to lift heavy objects to higher or lower ground. They are also used to bridge gaps between uneven surfaces. An inclined plane is called a simple machine because it makes moving a load easier. Inclined planes are sloping surfaces so anything that has a sloping surface makes up an inclined planes. Some examples of inclined planes include: a skateboarding ramp and screws.
Wedges
Wedges are another type of inclined plane. A wedge is made of two inclined planes. Wedges are used to split objects or stop them from moving. Wedges can also be used as a force multiplier. They concentrate the force of the object coming into contact with it and so the wedge is driven into the surface with more force. For example, a nail. Nails concentrate the force of the hammer so that the nail is driven deep into a wooden object with little effort. Other examples of wedges include: axes, chisels and teeth.
Inclined planes, also known as ramps, are used to lift heavy objects to higher or lower ground. They are also used to bridge gaps between uneven surfaces. An inclined plane is called a simple machine because it makes moving a load easier. Inclined planes are sloping surfaces so anything that has a sloping surface makes up an inclined planes. Some examples of inclined planes include: a skateboarding ramp and screws.
Wedges
Wedges are another type of inclined plane. A wedge is made of two inclined planes. Wedges are used to split objects or stop them from moving. Wedges can also be used as a force multiplier. They concentrate the force of the object coming into contact with it and so the wedge is driven into the surface with more force. For example, a nail. Nails concentrate the force of the hammer so that the nail is driven deep into a wooden object with little effort. Other examples of wedges include: axes, chisels and teeth.