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Work Done by Constant Force

The work is done when an object is displaced from its place due to acts of force. Work is defined in science as a force that causes an object to move.

We all are well aware of the definition of the work. The work is said to be done when an object displaces from its place due to acts of force. Work is defined in science as a force that causes an object to move. Work is the scalar product which means it only has magnitude and has no direction. The applied force and the displacement caused by this force in the case of a constant force. 

Define work done with constant force?

The work done is denoted as the multiplication of the distance covered by a body in the force and force direction.

W = F x d

Where F is the force and d is the displacement of the object.

Example: Let us assume that an object is kept on the surface having no friction, and a force of uniform magnitude of 20 N is working on it. Now, due to acts of force, the object will travel a distance of 10m, the work done is denoted as 

W = F x d

W = 20N x 10m = 200nm

Positive, negative, and zero work done

Negative Work: Work is considered negative when the force and the displacement are in opposite directions. For example, if an object is thrown towards the sky, its displacement will occur, while the acceleration due to gravity will pull the object towards the ground.

Examples 

  • When a ball is tossed into the air, it moves in the opposite direction of gravity.
  • The frictional force working against the action of the feet when walking on the road is negative work.
  • When pulling water out of the well, the force given to the rope is downward, but the bucket is hauled upward.
  • When one jumps, the gravitational force performs negative work.
  • A tug of war game is an example of a negative effort in which the opposing team uses force in the opposite direction.

Zero Work: If the force and displacement directions are perpendicular to one another, the force on the item does not work. When we push the wall forcefully, the pulling force on the wall produces no work because the wall’s displacement is d = 0. On the other hand, our muscles use our internal energy in this process, and as a result, we become exhausted.

Examples

  • When a person is pushing the wall
  • When an coolie carries the heavyweight 

Positive Work: Positive work occurs when an object is displaced by force acting in its direction. An example of this type of work is the motion of an object falling towards the ground, where the object’s displacement is in the direction of gravity.

Examples of the positive work done.

  • The football is kicked in the direction of motion by the players.
  • The patient is being moved in a wheelchair by a nurse.
  • A boy riding a skateboard.
  • Vehicles are moving forward on the road.
  • Lifting and shifting the chair in a different direction.
  • A box is being moved across the table.
  • A ball is thrown between two children.

Work Done by Constant Force

Work done by the uniform force is proportional to a force inserted times the displacement of any particle. An object could be increased or decreased to a smaller amount in a circle of the gravitational force. As the width is small, we suppose the gravitational forces are constant. 

F = mg 

(where g is gravitational constant, and F is also constant.)

It denotes that a force’s direction and magnitude are not varying. Hence, the force is said to be a constant force.

Suppose the force F be implemented at a certain point A of a particle along with AB & due to that, the moving body from point A to point B covers some distances.

Now, the work done = the magnitude of a force × magnitude of displacement.

Mathematically, W = F × s

Work done by the constant force in terms of conservation and non-conservation force

Conservation Force: Conservative force is a type of force that moves an object from one place to another. This force is independent of the path covered by an object and depends upon the initial and final point. Hence, we can conclude that work done by the conservative force only depends on the initial and final point and is independent of the path covered by it.

Non-conservation force: The non-conservative force depends on the area covered by a body and the final and initial position of the particle. The force of Friction is one of the most common examples of the non-conservative force. The force is called a non-conservative force when it results in a change of mechanical energy. The resultant is the sum of kinetic and potential energy. Non-conservative force removes and adds mechanical energy from the process.

Conclusion

In the above article, we have discussed the work done by a constant force. It is one of the most vital chapters of physics. Work is one of the essential processes in our daily life and science. There are various examples of work done in our day-to-day life. For example, a bull pulling a plough in a piece of land, a man pushing a cart in a mall, a student putting his school bag on his shoulder, and many more are examples of the work done.

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What do you mean by negative work?

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