# Tangential Acceleration vs. Centripetal Acceleration: What's the Difference?

Edited by Aimie Carlson || By Janet White || Published on January 4, 2024
Tangential acceleration is the rate of change of velocity along a curve's tangent, whereas centripetal acceleration is the rate of velocity change towards the curve's center.

## Key Differences

Tangential acceleration refers to the change in speed of an object moving along a curved path. It acts along the tangent to the path. Conversely, centripetal acceleration is the rate at which an object's velocity changes direction towards the center of the curve. It does not affect the object's speed but only its direction.
In circular motion, tangential acceleration is responsible for changing the magnitude of the velocity, not its direction. It's zero for uniform circular motion. On the other hand, centripetal acceleration always points towards the center of the circle and ensures that the object follows a curved path, without influencing its speed.
Tangential acceleration can exist independently of circular motion and applies to any change in speed along a curve. In contrast, centripetal acceleration is specific to circular or curved motion, acting perpendicular to the tangential acceleration and towards the curve's center.
When an object speeds up or slows down on a curve, tangential acceleration is at play. It's a vector quantity, dependent on the rate of speed change. In contrast, centripetal acceleration, also a vector, is constant in magnitude for uniform circular motion and always directs towards the curve's midpoint.

## Comparison Chart

### Definition

Rate of change of speed along a curve's tangent
Rate of velocity change towards a curve's center

### Direction

Along the tangent to the curve
Towards the center of the curve

### Effect on Motion

Changes the speed of the object
Changes the direction of the object's motion

### Presence in Uniform Motion

Zero in uniform circular motion
Present and constant in magnitude in circular motion

## Tangential Acceleration and Centripetal Acceleration Definitions

#### Tangential Acceleration

Change in speed along a curve's tangent.
As the car accelerated on the curved road, its tangential acceleration increased.

#### Centripetal Acceleration

Component of acceleration that changes the direction of velocity, not its magnitude.
In a loop-the-loop, the roller coaster experiences centripetal acceleration at the top of the loop.

#### Tangential Acceleration

Measure of how quickly an object's speed changes along a curved trajectory.
The tangential acceleration of the ball increased as it rolled faster down the curved ramp.

#### Centripetal Acceleration

Acceleration necessary for circular motion.
The spinning top maintains its circular path due to centripetal acceleration.

#### Tangential Acceleration

Velocity's rate of change along the direction of travel.
The skier's tangential acceleration varied as she navigated through the curved slope.

#### Centripetal Acceleration

Force causing an object to follow a curved path.
The centripetal acceleration kept the car on its circular track despite its speed.

#### Tangential Acceleration

Acceleration component parallel to an object's instantaneous motion on a path.
The cyclist's tangential acceleration was evident as he pedaled harder on the track.

#### Centripetal Acceleration

Acceleration towards the center of a curved or circular path.
The moon's orbit around Earth involves constant centripetal acceleration.

#### Tangential Acceleration

Rate of velocity change in the direction of motion.
The roller coaster experienced tangential acceleration as it sped up on the descent.

#### Centripetal Acceleration

Rate at which an object's velocity points increasingly towards the center of curvature.
The planet's orbit around the sun is a result of continuous centripetal acceleration.

## FAQs

#### Does tangential acceleration affect direction?

No, it only changes speed.

#### What does centripetal acceleration do?

It causes velocity change towards the curve's center, altering direction.

#### What is tangential acceleration?

It's the rate of change of velocity along a curve's tangent, affecting speed.

#### Can an object have both accelerations at once?

Yes, in curved motion, like a car turning at increasing speed.

#### Can centripetal acceleration exist without circular motion?

No, it's specific to circular or curved paths.

#### How does tangential acceleration vary in non-uniform motion?

It changes as the object's speed changes along the curve.

#### Is tangential acceleration present in uniform circular motion?

No, it's zero in uniform circular motion.

#### How does speed affect centripetal acceleration?

Higher speed requires greater centripetal acceleration for the same radius.

#### Is centripetal acceleration always perpendicular to velocity?

Yes, it's always directed towards the center, perpendicular to velocity.

#### Does tangential acceleration have a specific direction?

Yes, along the tangent to the path of motion.

#### Is centripetal force the same as centripetal acceleration?

No, centripetal force causes centripetal acceleration.

#### Does centripetal acceleration change in non-uniform circular motion?

Its magnitude may change if the speed changes.

#### What role does radius play in tangential acceleration?

It doesn't directly affect tangential acceleration.

#### Can centripetal acceleration be felt?

Yes, as the sensation of being pulled inward in a curve.

#### Does tangential acceleration require a force?

Yes, a force in the direction of motion is needed.

#### What causes centripetal acceleration?

Any force that pulls an object towards a curve's center.

#### What happens to tangential acceleration when an object slows down?

It remains, indicating deceleration along the curve.

#### Can tangential acceleration be negative?

Yes, when an object is slowing down.

#### Is centripetal acceleration constant in uniform circular motion?

Yes, its magnitude remains constant.