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A Quick Guide on Work Done in Rotation

Work done in rotation in the field of kinetics is referred to as the “Work-Kinetic Theorem” associated with rotation for a given object in motion.

In delving into the study, an exploration is conducted on the concepts associated with work done in rotation. The study further caters for determining the dynamics and kinematics for rotation that are acknowledged within the rigid bodies. It needs to be noted that rigid bodies are basically defined as bodies positing uniform motion that is made up of molecules and atoms. Moreover, the study will successively conduct a discussion that shows how angular momentum is intricately linked with work done by bodies’ exhibition of rotational motion. 

Main Body 

Overview of the Notions Involved in Work Done in Rotation

In order to understand the concepts associated with work done in rotation, the transference of energy is effectively measured. An extensive study is conducted that shows an intricate relationship between motions associated with angular and rotational aspects. Work done in rotation is determined by the amount of energy transferred on moving of an object with the help of an external force, torque from one place to another. In simpler terms, work done by a rigid body is determined by the sums of torques that are to be integrated over displacement associated with angular motion within an angle “θ” around a fixed axis of rotation. The work done in rotational motion is effectively linked with the theorem of work-kinetics.

What are Rotational Motions?

In kinetics, a body is stated to exhibit rotational motion when the motion follows a pattern, where all its particles move along a circular pathway. It should also be noted that the rigid body needs to move along a fixed axis with a similar angular velocity. Furthermore, the occurrence of rotation of the particle should be around a fixed point within space. The next example noticed for the rotational motions is the earth rotating about its axis pointing at a fixed speed.

Equation for Rotational Motion

The equation that is derived from the notions associated with the rotational motion in kinematics is as follows.

V = V0 + at, this equation represents linear motions, where “a” is denoted as constant, and the angular acceleration can be denoted as alpha. Now the equation for kinematics is, “ω=ω0+αt”, where “ω0” denotes angular velocity in the initial stages.

Rotational Work Formula

The term rotational work formula can be determined as addition of all the external torques that are applied to the rigid body; when rotated over an angle, it is said to be some quality work done by the given body. It also needs to be noted that, the theorem for work-energy, determines total work done that is equal to the energy associated with the rotational kinetic for the given rigid body.

Determining Angular Work

In determining angular work, it is stated to focus on uniform circular motions associated with the given body. In simpler terms, the angular velocity is determined by the angular displacement that is divided by the change in the time intervals noticed for the body in motion. It also needs to be noted that net torque needs to be zero for conserving angular momentum.

Angular Work Formula

In order to determine the formula associated with angular work, work done is primarily calculated, is determined by force acted upon the “dot product of force” and displacement caused by the application of force at a point. Furthermore, in conducting an angular motion, notions of force are replaced by external torque. On the other hand, linear displacements are actively replaced by angular displacements that are exhibited by the body in motion. It is expressed as, “W (torque) = Δ K* E (rotation)” respectively.


Gradually reaching this far in the study, it is noticed that an effective discussion has been catered to that will support determining a broader view concerning work done in rotational motion. Furthermore, within the study, the relationship between angular momentum to the work done is provided to a broader view, with the support of both formulas associated with angular work and that of rotational work. In addition to these, “Work-Kinetic Theorem” for rotation has also been discussed in order to clear concepts. Equations associated with rotational motion for a body are also defined that have further made the study quite interesting.


Frequently asked questions

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