Work-Definition

Everyday tasks include carrying heavy objects, using a bicycle, operating a mill, breaking stones, etc. In each piece, an item is subjected to a force that causes it to move from its original position. "Work is only deemed to have been accomplished scientifically when displacement has been produced in the object by applying force to it."

Scientifically, we may state that no work is done if an item is not moved when a force is given. For instance, there is no displacement in the object while we stand still with a weight on our heads; hence we are not exerting any effort. Yes, raising the burden and putting it on the head required exertion against the pull of gravity. It is evident that labor results in profit rather than effort. Internal work refers to these non-profitable tasks.

Kind of work

There are many different sorts of work, all of which have been described below, depending on factors such as the nature of the labor. According to its nature, the work is split into the following sections.

• A positive work done
• A negative work done
• Zero work done

Positive work done

Positive work is done in the direction of the object's motion. Work done is positive if the force is applied in the same direction as the direction of motion of the object.

For example, an object hitting the ground will fall in the direction of gravity. This is called positive work because gravity acts on the falling object.

W = ( + ) F * d

Below are examples of positive work that can help you understand more about it:

• A player of football kicking the ball in the direction of travel.
• A nurse pushes a patient in a wheelchair.
• A person riding a skateboard.
• Vehicles travelling on the road.
• Cut vegetables with a knife.
• Lift the chair and move it in another ddirection
• A box is pushed out onto the table.
• Two children throw balls at each other.

Negative Work Done

Negative work is done in the direction opposite to the movement of a body. If the force acts in the opposite direction to the motion of the object, the work done is negative.

When an object is thrown upwards, the motion of the object opposes the downward pull of the earth's gravity. Therefore, a completed job is a negative completed job.

W = (-) F * d

Here are some examples showing negative work:

• When you throw a ball in the air, it moves against gravity.
• The frictional force that counteracts the movement of your foot while walking around town is negative work.
• When you draw water from a well, the force on the rope acts downward, but the bucket rises.
• A seesaw is another example of negative effort because the force acts downward, and the person sitting opposite moves up.
• Gravity works negatively when a person jumps.
• If you catch a distant object with force, your hand will drop.
• Tug of war games are fun.

Zero work

If a body's displacement is perpendicular to the force exerted on it, no work is done.

When pressure and displacement are perpendicular to every difference or whilst both pressure or displacement is zero, the painting completed is stated to be zero.

Newton's first law of motion states that until an unequal force acts upon it, everything in the universe is at rest or in uniform motion (constant velocity).

Do you want to view the work's expression? Even with the same size F and s, the work's value varies depending on the angle.

When cos = 1 or the F and s directions are parallel, the body can be worked on the most. When the angle between force and displacement is 90°, the work done on the body is zero for cos=0. When the work done is zero, it is referred to as zero work.

Examples of zero work:

• A simple example of zero work is standing with your hands on your hips and not moving your backpack. Your hand exerts a force on the bag to balance its gravity, but the bag is not moving, so both the work (force) you are doing and gravity is zero.
• The work done by an object in uniform motion is zero. As already mentioned, work done on an object changes its kinetic energy. Therefore, if an object moves at a constant speed, its kinetic energy is constant. This means that you are doing nothing to your body.
• When an object moves on a horizontal plane, the direction of gravity on the object is downward, perpendicular to the object's displacement direction, so no gravity acts.