If you're seeing this message, it means we're having trouble loading external resources on our website.

Jeżeli jesteś za filtrem sieci web, prosimy, upewnij się, że domeny *.kastatic.org i *.kasandbox.org są odblokowane.

Główna zawartość

Rotational kinetic energy review

Overview of key terms, equations, and skills related to rotational kinetic energy, including the difference between rotational and translational kinetic energy.

Pojęcia kluczowe

Term (symbol)Meaning
Rotational kinetic energy (K)Kinetic energy due to rotational motion. Scalar quantity with SI units of Joules (J).


EquationSymbolsMeaning in words
K=12Iω2K is rotational kinetic energy, I is rotational inertia, and ω is angular velocityRotational kinetic energy is directly proportional to the rotational inertia and the square of the magnitude of the angular velocity.

Często spotykane błędy i nieporozumienia

Sometimes people forget that objects can have both rotational kinetic energy and translational (linear) kinetic energy. For example, a ball that is dropped only has translational kinetic energy. However, a ball that rolls down a ramp rotates as it travels downward. The ball has rotational kinetic energy from the rotation about its axis and translational kinetic energy from its translational motion.

Dowiedz się więcej

For deeper explanations on this topic, see our video on rotational kinetic energy.
To check your understanding and work toward mastering these concepts, check out our exercise on comparing rotational kinetic energy for different objects.

Chcesz dołączyć do dyskusji?

Na razie brak głosów w dyskusji
Rozumiesz angielski? Kliknij tutaj, aby zobaczyć więcej dyskusji na angielskiej wersji strony Khan Academy.