Peoples Physics Concepts

5.3. Centripetal Acceleration http://www.ck12.org

5.3 Centripetal Acceleration

• Describe centripetal acceleration, where it applies and how to calculate it.


• Explain when a force is acting as a centripetal force and how to apply it.

Students will learn what centripetal acceleration is, where it applies and how to calculate it. Students will also learn
when a force is acting as a centripetal force and how to apply it.

Key Equations

Centripetal Force

FC=

mv^2

r







m mass (in kilograms, kg)

v speed (in meters per second, m/s)

r radius of circle

Centripetal Acceleration

aC=

v^2

r

{

v speed (in meters per second, m/s)

r radius of circle

Guidance

If a massmis traveling with velocity~vand experiences a centripetal — always perpendicular — force~Fc, it will

travel in a circle of radius

r=

mv^2

|~F|

[1]

Alternatively, to keep this mass moving at this velocity in a circle of this radius, one needs to apply a centripetal

force of

~Fc=mv

2

r

[2]

By Newton’s Second Law, this is equivalent to a centripetal acceleration of:

~Fc=m~ac=mv

2

r

[3]