Kinetic Energy Is: Definition, Dimensions, Formulas, and Example Problems

Kinetic Energy Is: Definition, Dimensions, Formulas, and Example Problems
Kinetic Energy Is: Definition, Dimensions, Formulas, and Example Problems

Kinetic Energy Is: Definition, Dimensions, Formulas, and Example Problems – Kinetic energy in high school or equivalent is often studied in physics, of course this is related to doing calculations using formulas. If you want to learn it, please understand the following discussion below.

Definition of Kinetic Energy

Kinetic energy is the energy of motion, also known as energy in motion or energy associated with the motion of an object.

In this case, what is meant by kinetic energy is the energy contained in the objects that make movement, or kinetic energy, that is, the energy that others possess due to the movement they make. So the kinetic energy of an object can be interpreted as the work required to move an object with a certain mass, from the object in its internal state until it is moving at a certain speed.

It can also be called Energy of Motion, the name of kinetic energy itself comes from the Greek “Energeia” which means “Effort” and “Kinesis” which means “Movement”, to point out that kinetic energy can be influenced by two factors, namely, the dough. and movement speed that thing.

The term kinetic energy comes from the Greek words kinesis (motion) and energeia (active work). It generally means, “Through the movement of doing active work.” More simply, anything, an object, object, etc. that has mass and is moving will have some kind of kinetic energy. For example, thermal energy exists due to the movement of atoms or molecules, so thermal energy is a variation of kinetic energy.

Potential Energy: Potential energy is energy that affects objects due to the position (height) of the object where the trend is toward infinity in the direction of the force generated by the potential energy. The SI unit for measuring work and energy is the Joule (symbol J).

Density is a measure of the mass per unit volume of an object. The greater the density of an object, the greater the mass of each volume. The average density of each object is the total mass divided by the total volume. An object that has a higher density (for example, iron) will have a smaller volume than an object with the same mass that has a lower density (for example, water).

The SI unit of density is the kilogram per cubic meter (kg m-3).

Density is used to determine the substance. Each substance has a different density. And a substance regardless of mass regardless of volume will have the same density.

Also read: Definition of insulators, conductors and semiconductors according to physicists

Examples of kinetic energy in daily life

&Quot;Kinetic Energy&Quot; Definition & (Examples - Formulas)

So here are some examples of kinetic energy that can be found all around us, including:

  • River water moving/flowing at a certain speed has kinetic energy, because flowing water has mass and speed as well.
  • Meteors that fall to the earth’s surface have kinetic energy because meteors have mass and fall at high speed to the earth’s surface.
  • Someone riding a bicycle on the road, of course the bicycle has mass and will move from one place to another.
  • A truck that has mass travels or travels at a certain speed.
  • A soccer ball that rolls until it moves from one place to another.
  • Writing utensils such as pencils or pens that fall off the table.
  • A stone thrown by a catapult spring.
  • People riding motorcycles on the road.
  • A train traveling at a certain speed.
  • Fruit falling from the tree.
  • Electrical energy into motion energy as in fans, mixers, blenders and others.
Read More :   cottonville

Also read: Understanding And 100 Light Sources And Their Benefits According To Experts

Kinetic energy formula

In the case based on the following formula, if the object is moving faster, the kinetic energy it has will be larger, and if the mass of the object is large, the kinetic energy is also large.

So here is the formula for kinetic energy you need to know:

E k = 1/2. meter. v2


  • I: kinetic energy “Joule”
  • m : mass “Kg”
  • v : speed “m/s”

Also read: 10 definitions and properties of metals according to physicists

Examples of Kinetic Energy Problems

First question

You go to work driving a motorcycle with a speed of 4 m/s, your motorcycle has a mass of 115 kg, what is the kinetic energy of your motorcycle?


E k = 1/2. meter. v2

E k = 1/2. 115kg (4m/s) 2

Ek = 920 joules

So, the kinetic energy of your bike is 920 Joules.

Also read: Definition and 4 types of potential energy

Second question

Budi rolls a stone on the ground, the kinetic energy of the stone is 25 joules and its mass is 3 kg, what is the speed of the stone?

It is known:

Ek = 100 Joules gives m = 3 Kg

Asked = v..??


  • 25 = 1/2 x 3 x v2
  • 25 = 1.5v2
  • v2 = 25/1.5
  • v2 = 16.6
  • v = √16.6
  • v = 4.07m/s

So the result of the rolling speed of the stone is 4.07 m/s.

Also read: The process of a lunar eclipse according to experts


From the above description, we can conclude that the notion of kinetic energy is the energy contained in moving objects. Kinetic energy is also called energy of motion, the name itself comes from the Greek word “Energeia” meaning “work” and the word “kinesis” meaning “motion”.

Examples of kinetic energy around us such as:

  • A truck that has mass and travels at a certain speed.
  • A ball in motion rolls in such a way that it moves from one place to another.
  • Writing utensils such as pencils or pens that fall off the table.
  • Throwing stones and others.

Also read: 223 Definition and types of energy according to experts

There are three types of systems depending on the type of exchange that occurs between the system and the environment:

  • isolated system: there is no exchange of heat, matter or work with the environment. An example of an isolated system is an insulated container, such as an insulated gas cylinder.
  • closed system: there is exchange of energy (heat and work) but there is no exchange of objects with the environment. A greenhouse is an example of a closed system in which heat is exchanged but no work is exchanged with the environment. Whether a system exchanges heat, work, or both is generally considered a limiting property:

  1. adiabatic barrier: does not allow heat exchange.
  2. Rigid barrier: does not allow job vacancies.
  • open system: there is an exchange of energy (heat and work) and objects with their environment. A barrier that allows the exchange of objects is called permeable An ocean is an example of an open system.
    – The pressure in liquids for the Physics level of 8th Grade is divided into several topics, namely: Hydrostatic Pressure, Pascal’s Law, Related Vessels and Archimedean Force. This time we will talk about the four components in general.
Read More :   Download Subway Surf Mod APK Complete All Characters Latest 2020

Also read: The Process of Occurrence of a Solar Eclipse According to Experts

hydrostatic pressure

Hydrostatic pressure is the pressure in a liquid at rest. The magnitude of hydrostatic pressure depends on the type and depth of the liquid, not the shape of the container (as long as the container is open).

The amount of hydrostatic pressure is formulated by:

Hydrostatic Pressure


P = pressure (Pa or N/m2))
p = mass of liquid type (kg/m3)
g = acceleration due to gravity (m/s2 or N/kg)
h = depth (m) Sample question:

A pond 2 meters deep is filled with water (torque = 1000 kg/m3). If the acceleration due to gravity is 10 m/s2, what is the hydrostatic pressure at a point 20 cm from the bottom of the pool?


p = 1000kg/m3
g = 10m/s2
h = (2 – 0.2)m = 1.8m

Thus, P = pgh = 1000. 10. 1.8 = 18,000 Pa

Also read: style and movement

Pascal’s Law

Pascal's Law

When you push the small suction cup, the suction cup receives a force of F1 in the area of ​​A1, resulting in a pressure of p1. According to Pascal, this pressure will be transmitted in all directions equally, so the pressure will be transmitted equally to the large suction cup. Therefore, even at a large suction there is a pressure equal to p1. This pressure causes a force in the area of ​​the second suction press (A2) of F2 so you can write the following equation.

So the force exerted on the large suction cup is:

From the equation , it can be concluded that to obtain a large force effect from a small force, the cross-sectional area must be enlarged. This is the simple working principle of a car lifting engineering device called a hydraulic pump.

connected boat

The principle of related craft is an event that the surface of the water is always level. In this case, it is not affected by the shape of the bottom surface or the shape of the tube, as long as the water is in contact. The laver app relates in everyday life!

Read More :   Toby Dorr Son: What happened to Toby Dorr Son? Who is Toby Dorr?

Builders use the concept of connected containers to create points of equal height. These two points of the same height are used to create a flat straight line. This line is usually used as a reference point for laying tiles so that the surface of the tiles is even and installing windows so that the windows are parallel to each other.

The builder uses a small hose that is filled with water and directed up at both ends. Two water surfaces will be produced, namely the water level at both ends of the hose. A thread is then stretched connecting the two water surfaces at both ends of the hose. This way the builder will get a flat surface.

Also read: Understanding and history of physics according to research theory

Pay attention to the water jug ​​in your house. The kettle is a connected container. A good water pitcher should have a higher mouth than the water pitcher.

Water shelters Usually, each house has a water tank. This water tank is placed in a high place, such as the roof of a house. If observed, a sufficiently large container of water is connected to the faucet where the water comes out through pipes. If the shape of the pot related to the above explanation forms the letter U, the pot in this water tank does not have that shape. It is deliberately designed that way because this system aims to drain the water to a lower place with quite a large beam power.

The magnitude of this buoyant force depends on the amount of water pushing on the object. The more water that is forced, the greater the buoyancy. The results of his discovery are known as Archimedes’ Law, which states that when an object is immersed in a liquid, either partially or completely, the object will receive a buoyant force (upward force) that is equal to the weight of the liquid. displaced by the object. Mathematically written as follows.

Also read: Understanding And 100 Light Sources And Their Benefits According To Experts

Where: = buoyant force (N), = density of the liquid (kg/m3), V = volume of fluid displaced or volume of submerged object (m3), g = constant of gravity or acceleration of gravity (m/s2) .

Yhs-Fully Hosted_003, formula for pressure of liquids, pressure on liquids, pressure on liquids, formula for pressure on liquids, formula for pressure of water, formula for liquids, definition of pressure in liquids, water flowing through the thread of a teapot or tub of any event in science, the pressure in the liquid.

That’s the discussion about Kinetic Energy Is: Definition, Dimensions, Formulas, and Example Problems I hope that this review can bring information and knowledge to all of you, thank you very much for your visit. 🙂 🙂 🙂

Maybe below is what you need