6.2.3 Relating Angular and Linear Quantities

Question 1

Relating Angular and Linear Quantities

Answer 1

• To describe the motion of a rotating object as a whole, all you need are the values of its angular position (q), angular velocity(w), and angular acceleration (a).
• If you are interested only in the motion of a particular part of a rotating object, you can convert from angular to linear variables using these formulas:; ; ; .
• The total linear acceleration is the vector sum of the centripetal acceleration (ac) and tangential acceleration (at)

Question 2

Imagine a ladybug on a spinning record. Where is its angular speed the greatest?

Answer 2

The angular speed is the same everywhere

Question 3

The Earth makes one revolution every 23.93 h, and has an equatorial radius of 6,380 km. Which of the following is the tangential speed of Quito, Ecuador, a city near the equator?

Answer 3

465 m / s

Question 4

Consider a wheel rotating counterclockwise as seen from above. Which of the following denotes the direction of the acceleration of Point P if the wheel is speeding up?

Answer 4

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