ch11-p090 - 90. The speed of the center of mass of the car...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 90. The speed of the center of mass of the car is v = (40)(1000/3600) = 11 m/s. The angular speed of the wheels is given by Eq. 11-2: ω = v/R where the wheel radius R is not given (but will be seen to cancel in these calculations). (a) For one wheel of mass M = 32 kg, Eq. 10-34 gives (using Table 10-2(c)) 1 11 = Iω 2 = MR 2 2 22 Krot FG H IJ FG v IJ K H RK 2 = 1 Mv 2 4 which yields Krot = 9.9 × 102 J. The time given in the problem (10 s) is not used in the solution. (b) Adding the above to the wheel’s translational kinetic energy, K wheel = 1 2 Mv 2 , leads to 1 1 3 2 Mv 2 + Mv 2 = ( 32 kg )(11 m/s ) = 3.0 × 103 J. 2 4 4 (c) With Mcar = 1700 kg and the fact that there are four wheels, we have 1 3 M car v 2 + 4 Mv 2 = 12 × 105 J. . 2 4 FG H IJ K ...
View Full Document

This note was uploaded on 05/17/2011 for the course PHY 2049 taught by Professor Any during the Spring '08 term at University of Florida.

Ask a homework question - tutors are online