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Kinetic energy definition

Kinetic energy $$(E_{\text{k}})$$ is the energy that an object possesses due to its movement (its speed) and its mass.

Doing work on an object can give it kinetic energy.

To accelerate a stationary object so that it has $$100 \text{ J}$$ of kinetic energy, you need to do $$100 \text{ J}$$ of work.

Objects that are heavier or moving faster are harder to stop. This means they have more kinetic energy.

A car travelling at $$30 \ukmph$$ has less kinetic energy than a car travelling at $$60 \ukmph.$$

An object's kinetic energy can be calculated using the formula: $$$\Torange{\text{kinetic energy}}=\frac{1}{2}\times\Tblue{\text{mass}} \times \Tred{\text{speed}^{2}}$$$

Kinetic energy is also often abbreviated as $$KE$$ or $$T$$.

A car of mass of $$1000 \text{ kg}$$ travelling at a speed of $$20 \umps$$ has a kinetic energy of $$200,000 \text{ J}.$$
A car of mass of $$1000 \text{ kg}$$ travelling at a speed of $$20 \umps$$ has a kinetic energy of $$200,000 \text{ J}.$$