Write short notes on the following terms
Levers
Mechanical advantage
Velocity ratio
Levers: Levers are simple machines consisting of a rigid bar or board that rotates around a fixed point called the fulcrum. They are used to transmit and amplify force or perform tasks with less effort. There are three types of levers: first-class lever (fulcrum between input force and output force), second-class lever (output force between fulcrum and input force), and third-class lever (input force between fulcrum and output force). Examples of levers include seesaws, scissors, and crowbars.
Mechanical advantage: Mechanical advantage is a measure of the amplification of force achieved by a machine. It is the ratio of the output force exerted by a machine to the input force applied to it. A machine with a high mechanical advantage requires less input force to do the same amount of work as a machine with a lower mechanical advantage. It is calculated by dividing the output force by the input force. Mechanical advantage allows us to accomplish tasks that would otherwise be difficult or impossible using only our own strength.
Velocity ratio: Velocity ratio is a measure of the speed advantage gained by a machine. It is the ratio of the distance an input force is applied to the distance an output force is moved. In other words, it compares the distance covered by the input force to the distance covered by the output force. The velocity ratio indicates how much faster an object can be moved by a machine compared to manually doing the task. It is calculated by dividing the distance moved by the output force by the distance moved by the input force.
Levers:
- Levers are simple machines that consist of a rigid bar or beam that pivots on a fixed point called a fulcrum.
- They are used to exert force or change the direction of force applied to an object.
- Levers can be classified into three types based on the relative position of the fulcrum, load, and effort: first-class, second-class, and third-class levers.
- First-class levers have the fulcrum positioned between the load and the effort. Examples include a seesaw and a pair of pliers.
- Second-class levers have the load between the fulcrum and the effort. Examples include a wheelbarrow and a nutcracker.
- Third-class levers have the effort between the fulcrum and the load. Examples include a fishing rod and a shovel.
Mechanical Advantage:
- Mechanical advantage is a measure of the amplification of force provided by a machine.
- It refers to the ratio of the output force produced by a machine to the input force applied to it.
- A machine with a mechanical advantage greater than 1 provides an output force larger than the input force, thus increasing the effectiveness of work.
- Mechanical advantage can be calculated using the formula: mechanical advantage = output force / input force.
- The greater the mechanical advantage, the easier it is to perform work using the machine.
- There are different ways to increase mechanical advantage, such as increasing the length of the lever arm or using pulley systems.
Velocity Ratio:
- Velocity ratio, also known as the mechanical advantage in terms of speed, is a measure of how much the speed of an object is increased or decreased by a machine.
- It refers to the ratio of the distance or speed of the effort to the distance or speed of the load.
- Velocity ratio can be calculated using the formula: velocity ratio = distance or speed of effort / distance or speed of load.
- A velocity ratio greater than 1 means that the machine increases the speed of the load, while a ratio less than 1 means that the machine decreases the speed.
- Velocity ratio is different from mechanical advantage as it focuses on the speed aspect rather than the force aspect of a machine.