Circular Motion

Front

Uniform Circular Motion Noun

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[yoo-nuh-form sur-kyuh-ler moh-shuhn]

Back

Uniform Circular Motion

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The motion of an object traveling at a constant tangential speed on a circular path, resulting in continuous acceleration.

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Example: This diagram shows an object moving in a circle. The blue arrow (velocity) is always changing direction, while the red arrow (acceleration) always points to the center.

Front

Angular Displacement Noun

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[ang-gyuh-ler dis-pleys-muhnt]

Back

Angular Displacement

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The angle through which a point revolves around a center or a line has been rotated in a specified sense.

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Example: This diagram shows that angular displacement (θ) is the angle an object moves through when traveling in a circle of a certain radius (r).

Front

Angular Velocity Noun

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[ang-gyuh-ler vuh-los-i-tee]

Back

Angular Velocity

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The rate of change of angular displacement, specifying the rotational speed and direction of an object around an axis.

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Example: This diagram shows a car wheel's angular velocity (ω), the speed of its spin. It relates this to the car's forward linear velocity (v).

Front

Angular Acceleration Noun

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[ang-gyuh-ler ak-sel-uh-rey-shuhn]

Back

Angular Acceleration

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The time rate of change of angular velocity, indicating how quickly an object's rotation speed is changing over time.

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Example: Applying a force (F) to the edge of a bike tire causes it to change its speed of rotation, which is called angular acceleration (α).

Front

Tangential Speed Noun

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[tan-jen-shuhl speed]

Back

Tangential Speed

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The linear speed of an object moving along a circular path, directed tangent to the circle at any given point.

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Example: An object moving in a circle has a tangential speed, which is its speed at any instant, directed straight ahead and tangent to the circular path.

Front

Tangential Acceleration Noun

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[tan-jen-shuhl ak-sel-uh-rey-shuhn]

Back

Tangential Acceleration

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The component of acceleration directed tangent to a circular path, representing the rate of change of tangential speed.

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Example: This diagram shows a car moving in a circle. The arrow labeled 'a_t' is the tangential acceleration, which is responsible for changing the car's speed.

Front

Centripetal Acceleration Noun

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[sen-trip-i-tl ak-sel-uh-rey-shuhn]

Back

Centripetal Acceleration

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The acceleration of an object moving in a circular path, directed towards the center, resulting from a continuous change in direction.

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Example: A car turning in a circle experiences centripetal acceleration, which is directed toward the center of the curve and is responsible for changing the car's direction.

Front

Centripetal Force Noun

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[sen-trip-i-tl fawrs]

Back

Centripetal Force

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The net force required to keep an object moving in a circular path, always directed towards the center of the circle.

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Example: A force, like the pull from the string, that keeps an object moving in a circle by constantly pulling it toward the center of the path.

Front

Inertia Noun

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[in-ur-shuh]

Back

Inertia

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The property of an object to resist any change in its state of motion, whether at rest or moving uniformly.

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Example: This image does not explain inertia; it only lists the materials needed to perform a science demonstration related to linear inertia.

Front

Moment of Inertia Noun

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[moh-muhnt uhv in-ur-shuh]

Back

Moment of Inertia

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A quantity measuring a body's resistance to angular acceleration, which is the rotational equivalent of mass in linear motion.

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Example: This image shows that the moment of inertia depends on an object's shape and the axis around which it rotates.