Ideal Mechanical Advantage:
In a real machine, some of the work done by the input force is converted to thermal energy by the friction in the machine. Because of this, the work done by the output force is less than the work done by the input force. An ideal machine has no friction, and therefore no energy is converted to thermal energy. The mechanical advantage of a machine that has no friction is called the ideal mechanical advantage (IMA). The IMA can be calculated by finding the ratio between the distance over which the input force is exerted on the machine din and the distance over which the output force is exerted on the object Dout.
This shovel is a third class lever the right hand on the end is the fulcrum the left hand in the middle is the force applied to clear the snow and the snow it self is the load.
Sometimes, the IMA is less than one and the output distance is greater than the input distance. This usually means that the speed at the output is higher than the speed at the input. Examples of machines with an IMA less than one are hockey sticks, baseball bats, and garden rakes. In each of these machines, the distance moved by the input force is less than the distance moved by the output force. When an increase in speed of motion is required, an IMA of less than one is sometimes necessary.
How to Calculate the Ideal Mechanical Advantage:
IMA = Input distance over output distanceIMA = Din over dout
Suppose Priya uses a hammer to pull a nail as shown in the picture at the bottom. If she moves the handle of the hammer 30 cm and the nail moves 5.0 cm, what is the ideal mechanical advantage of the hammer?
IMA= din/doutIMA= 30cm/5.0cmIMA=6.0
Home Page Practice Questions Input vs Output
Ideal Mechanical Advantage:
In a real machine, some of the work done by the input force is converted to thermal energy by the friction in the machine. Because of this, the work done by the output force is less than the work done by the input force. An ideal machine has no friction, and therefore no energy is converted to thermal energy. The mechanical advantage of a machine that has no friction is called the ideal mechanical advantage (IMA). The IMA can be calculated by finding the ratio between the distance over which the input force is exerted on the machine din and the distance over which the output force is exerted on the object Dout.
Video on IMA
Ideal Mechanical Advantage of Less Than 1:
Sometimes, the IMA is less than one and the output distance is greater than the input distance. This usually means that the speed at the output is higher than the speed at the input. Examples of machines with an IMA less than one are hockey sticks, baseball bats, and garden rakes. In each of these machines, the distance moved by the input force is less than the distance moved by the output force. When an increase in speed of motion is required, an IMA of less than one is sometimes necessary.
How to Calculate the Ideal Mechanical Advantage:
IMA = Input distance over output distanceIMA = Din over dout
Suppose Priya uses a hammer to pull a nail as shown in the picture at the bottom. If she moves the handle of the hammer 30 cm and the nail moves 5.0 cm, what is the ideal mechanical advantage of the hammer?
IMA= din/doutIMA= 30cm/5.0cmIMA=6.0