In 8.5 s a fisherman winds 2.1 m of fishing line onto a reel whose radius is 3.0
ID: 1763309 • Letter: I
Question
In 8.5 s a fisherman winds 2.1 m of fishing line onto a reel whose radius is 3.0cm (assumed to be constant as an approximation). The line is beingreeled in at a constant speed. Determine the angular speed of thereel.1 rad/s
An auto race is held on a circular track. A car completes one lapin a time of 16.6 s, with an averagetangential speed of 48.4 m/s. Find thefollowing. (a) the average angular speed
1 rad/s
(b) the radius of the track
2 m
(a) the average angular speed
1 rad/s
(b) the radius of the track
2 m
Explanation / Answer
let the linear speed be v, for d=2.1m, we have: d = vt =>v=d/t = 2.1m/8.5s = (2.1/8.5) m/s the angular speed is: = v/r = (2.1/8.5)m/s /3.0*10-2 m = 8.24 rad/s An auto race is held on a circular track. A car completes onelap in a time of 16.6 s, with an averagetangential speed of 48.4 m/s. Find thefollowing. (a) the average angular speed the circular distance d = 2r since d = vt = 48.4m/s * 16.6s =>r = 48.4m/s *16.6s / 2*3.14 =127.94m angular speed = v/r = 48.4m/s / 127.94m = 0.378 rad/s(b) the radius of the track
r = 127.94m (a) the average angular speed the circular distance d = 2r since d = vt = 48.4m/s * 16.6s =>r = 48.4m/s *16.6s / 2*3.14 =127.94m angular speed = v/r = 48.4m/s / 127.94m = 0.378 rad/s
(b) the radius of the track
r = 127.94m