Rotational Kinematics – Precision Learning for Success | Verified Questions & A+ Answers

A+ Graded Paper
Rotational Kinematics: Precision Learning for
Success -Verified Questions & A+ Answers

Questions and Mark scheme


Version: Final

, [8.5] In which of the following is a tangential acceleration involved in the motion?

(a) A 1-kg mass swinging freely at the end of a rope

(b) The tip of a lawn mower blade running at constant 40 rev/s

(c) The outer edge of merry-go-round ride rotating at a constant 30o/s

(d) A runner running at a constant 4 m/s around a circular track - ✔✔a



the other answer choices mention constant



[8.5] What is the magnitude of the total acceleration of the tip of a 1.20-m airplane propeller that is moving with an
angular speed of 35.0 rad/s and undergoing an angular acceleration of 11.0 rad/s2?

(a) 42.0 m/s2

(b) 151 m/s2

(c) 138 m/s2

(d) 145 m/s2 - ✔✔centripetal acceleration = (1.20m) (11.0 rad/s^2)^2 = 145.2 m/s

tangential acceleration = (1.20 m) (35 rad/s) = 42 m/s



square root 145.2^2 + 42^2 = 151 m/s ^2



b



[8.6] A car is moving with a constant speed of 70.0 mi/h (31.2 m/s). If its wheels have a radius of 24.1 cm, what is their
angular speed?



(a) 1.30 rad/s

(b) 130 rad/s

(c) 65.0 rad/s

(d) 204 rad/s - ✔✔angular speed = tangential velocity / radius

= 31.2m/s / .241 m



b