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The Question & Answer (Q&A) Knowledge Managenet

The Internet has many places to ask questions about anything imaginable and find past answers on almost everything.

Table of Contents

- Is tangential acceleration always positive?
- Why is angular acceleration negative?
- Is tangential acceleration the same as angular acceleration?
- What is tangential acceleration equal to?
- What is tangential and normal components of acceleration?
- What is the normal component of the acceleration?
- Is radial and normal acceleration same?
- What is radial acceleration equal to?
- What is meant by radial acceleration?
- Is radial acceleration always negative?
- What is the difference between radial acceleration and centripetal acceleration?
- How do you find radial acceleration?
- What is the radial acceleration of the mercury?
- What is the acceleration of the Earth in its orbit?

Note that the tangential acceleration ¨ s can be either positive or negative, while the normal or centripetal acceleration is always positive, because the product ˙ s ˙ θ = v 2 / R is always positive ( s and θ both increase, if the motion is in the direction of the tangential unit vector, or both decrease if the motion …

Negative angular velocity(ω) means that the particle is revolving anticlockwise. Thus, negative angular acceleration(α) is a “push” in the anticlockwise direction. If α and ω have the same sign, the body will speed up, else slow down (and eventually go in reverse).

Angular acceleration is the change in angular velocity divided by time, while tangential acceleration is the change in linear velocity divided by time. People sometimes forget that angular acceleration does not change with radius, but tangential acceleration does.

In rotational motion, tangential acceleration is a measure of how quickly a tangential velocity changes. It always acts perpendicular to the centripetal acceleration of a rotating object. It is equal to the angular acceleration α, times the radius of the rotation.

The tangential component is the part of the acceleration that is tangential to the curve and the normal component is the part of the acceleration that is normal (or orthogonal) to the curve. If we do this we can write the acceleration as, →a=aT→T+aN→N.

The normal component of acceleration is also called the centripetal component of acceleration or sometimes the radial component of acceleration. To understand centripetal acceleration, suppose you are traveling in a car on a circular track at a constant speed.

Radial And Tangential Acceleration Radial acceleration is always along normal to the instantaneous velocity so it is also known as normal acceleration. The magnitude of the tangential acceleration is equal to the rate of change of speed of the particle w.r.t. time and it is always tangential to the path.

This is called the radial acceleration, or centripetal acceleration (“centripetal” means “center seeking”). The radial acceleration is equal to the square of the velocity, divided by the radius of the circular path of the object. The unit of the centripetal acceleration is meters per second squared ( ).

In a uniform circular motion, “the acceleration of the object is along the radius, directed towards the centre” is called radial acceleration.

For your acceleration case, the radial acceleration, ar , is negative (though without saying it’s part of the acceleration vector, this is a little unhelpful) and ac appears to just be the magnitude of the centripetal acceleration.

3 Answers. The radial acceleration, ¨r, is responsible to change the rate of change of the radius vector, ˙r, which in turn is responsible to change the magnitude r of the radius vector, its length. The centripetal acceleration −r˙θ2 is what makes the particle describe some curvilinear path.

Radial acceleration can be found by dividing the velocity squared by the radius. Radial acceleration = v2 /r . Radial acceleration occurs because of a change in direction of the velocity.

Bulk parameters

Mercury | Earth | |
---|---|---|

Ellipticity (Flattening) | 0.0000 | 0.00335 |

Mean density (kg/m3) | 5427 | 5514 |

Surface gravity (eq.) (m/s2) | 3.70 | 9.80 |

Surface acceleration (eq.) (m/s2) | 3.70 | 9.78 |

The acceleration due to gravity on earth is 9.8 m/s^2.