Mechanical work: Examples and Applications
In physics, it is called mechanical work that develops a force on an object and may affect its position or its amount of movement. In other words, mechanical work is the amount of energy necessary to set an object in motion, vary the characteristics of said displacement, or even stop it.
Although force and displacement are vector quantities, needing direction and sense, work is considered a scalar quantity, since it does not introduce variations in the direction and direction of the force that produces it.
In the event that the object is already in motion, the work will be carried out in the opposite direction to the trajectory of the displacement, managing to cancel or deviate the trajectory. In some cases, this may require vector representations.
The first model is considered positive or motor work, the second resistant or negative work.
So, in its simplest variant, mechanical work can be calculated according to the formula :
W (work in joules) = F (force in newtons). d (distance in meters).
Examples of mechanical work
- Push a table from one end of the room to the other.
- Pulling a plow like oxen do in the traditional field.
- Open a sliding window with constant force to the limit of its track.
- Pushing a car that has run out of gas.
- Carry a bicycle by hand without climbing on it to pedal.
- Pulling a door to enter a room.
- Towing a vehicle with another or with a crane that pulls it and moves it.
- Dragging someone by the arms or feet.
- Raise a piano with a string and pulley system.
- Raise a bucket full of water from the bottom of a well.
- Pick up a box full of books from the floor.
- Pull the cargo from the train by the locomotive that pulls forward.
- Tear down a wall by pulling on it with a high powered pickup or truck.
- Pull a rope at the other end of which other people are pulling (cinched).
- Support a collapsing wall by applying your own weight.
- Hold a helium balloon at ground level that tends to rise.
- Win a pulse by overcoming the force that the opponent exerts in the opposite direction.
- Lift a weight off the ground, as Olympic athletes do.
- Pulling a horse-drawn carriage, like those used in the past.
- Pulling a boat by an outboard motor, which moves it forward on the water.