## Kinetic, Rotational, Translational and Potential Energy Formulas

### 1. Rotational Kinetic Energy

Rotational kinetic energy is a solid object can be derived from translational kinetic energy note below:

m = mass of the object in kg

v = linear velocity of the object in m per s2

Ek = kinetic energy of the object in joules.

INGAT! v = ? R maka

Because mR2 is the moment of inertia, the rotational kinetic energy formula can be formulated as follows:

with:

Ecrot = rotational kinetic energy in

I = moment of inertia of the object in kg.m2

? = angular velocity in rad per s

Look at the following picture!

A force F can act at a distance R from the objectâ€™s axis of rotation.

s where W = work of internal rotation = moment of force in kg.

M? = angle to be formed in rad

In rotational motion a moment of force will do hard work on the object or change its rotational kinetic energy according to the relationship

In rotational motion, the law of conservation of mechanical energy will also apply if the resultant external force is zero, namely:

Ep + Ek tran + Ek rot = tetap

Ep1 + Ek tran 1 + Ek rot 1 = Ep2 + Ek tran 2 + Ek rot 2

### 2.Translational Kinetic Energy

The combination of translational or rotational motion that occurs in the cylinder to be pushed so that it can roll forward. The cylinder will rotate as well as translate. First, letâ€™s see when an object is said to perform pure translational motion and when to perform pure rotational motion. After that, Take a cylinder, apply a force on the edge of the cylinder so that the cylinder can rotate with the axis of rotation between the middle of the cylinder.

Whereas in pure translational motion, suppose a cylinder is pulled without rotation, so that there is only translational motion.

### How about the speed?

An object that will perform pure translational motion so all the points move with the same speed. See picture a above. The velocity at point A is equal to the velocity at point P is the same as the velocity at point B. Therefore, in pure rotational motion, opposite points can move linearly in opposite directions.

The velocity at point A is in the opposite direction at point B, the velocity at point P is 0, while the angular velocity at point A is the same as at point B. Therefore, in combined motion the velocity can be obtained by adding up the velocity vectors at point A, which is 2v , the velocity at point P is v and the velocity at point B is 0.

### Rolling motion is a combination of translational and rotational motion

The combined motion of translational motion and rotational motion is known as rolling. In the foregoing we consider a rotating particle having a kinetic energy of K is I?2. If the rotating object is a rigid body, then we can use the moment of inertia of the object in question. For a rolling object, the kinetic energy is the result of the sum of the translational kinetic energy and the rotational kinetic energy. The object that will carry out the rolling motion has a rotational equation and a translational equation. However, the amount of kinetic energy that an object will have rolling over is the sum of the rotational kinetic energy and translational kinetic energy. An object that performs translational and rotational motion at the same time is called rolling.

### 3. Potential Energy

When an object is moving, we can say that it has kinetic energy. However, objects will also likely have Potential Energy. Potential energy is the energy possessed by an object because of its position and shape. One example of potential energy is: gravitational potential energy and so on we also call Potential Energy. Potential energy can occur in the presence of gravitational force. An object will have a large potential energy if its mass is greater and its height is higher.

The formula for potential energy is denoted by:

EP= mghs

Where,

EP= Potential Energy of the object

g= velocity of gravity (9.8 m/s2)

h= height of object (m)

The business relationship with Potential Energy is denoted by:

W = Delta EP = mg

Where,

h_2 â€“ h_1 is the change in elevation

Thatâ€™s the material about **Rotational, Translational, and Potential Kinetic Energy Formulas** from **RumusRumus.com** may be useful.

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