Circular Motion Equations | Show Me The Physics

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At point P, the car hits an area of ice and loses all frictional force on its tires. Which path does the car follow on the ice?

June 2001 Regents

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Tangent to the semi-circle

Review - Velocity, Circular Motion

Given

Why is an object moving at constant speed in a circle considered to be accelerating?

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Because while its speed is not changing, its direction is.

1. Centripetal Acceleration (a_c) - acceleration toward center of curvature

Equation:

a_c = V² / r

r - radius,
V - velocity

b) (V) Instantaneous Velocity - tangent to circle, in the direction of the motion

c) Centripetal Force (F_c) - force directed toward the center of the circle

Given

A car moving in a circular path with a radius of 2.0 m has a velocity of 8.0 m/s.
Find: the centripetal acceleration of this car.

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a_c = V² / r
= (8.0 m/s)² / 2.0 m

a_c = 64 / 2

a_c = 32. m/s²

Giancoli p. 130) 2, 4

NYSSLS Reading Passage · Dynamics

The Centripetal Dynamic of the Gravitron

5 quick questions — pick an answer to see if you’re right.

1. Why is an object moving at constant speed in a circle considered to be accelerating?

2. A car moves in a circle of radius 2.0 m at 8.0 m/s. What is its centripetal acceleration?

3. What is the direction of the centripetal acceleration of an object in uniform circular motion?

4. An object moves at 10 m/s in a circle of radius 5.0 m. What is its centripetal acceleration?

5. A car on a curved track hits ice at point P and loses all friction. Which path does it follow?