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0593_C03_fm  Page 75  Monday, May 6, 2002  2:03 PM





                       Kinematics of a Particle                                                     75


                       P3.5.2: Consider the Earth to be a sphere with a radius of 3960 miles. Let P be a point on
                       the surface of the Earth at a latitude of 40˚, as represented in Figure P3.5.2. With the Earth
                       rotating on its axis one revolution per day, determine the magnitudes of the velocity and
                       acceleration of P.

                                                                       N
                                                                              P
                                                                    k

                                                                     O   40°




                       FIGURE P3.5.2
                       A point P on the surface of the Earth.          S


                       Section 3.7  Motion on a Circle
                       P3.7.1: A particle P is located on the rim of a flywheel as shown in Figure P3.7.1. If the
                       radius of the flywheel is 300 mm, and if the angular displacement θ, the angular speed
                       ω, and the angular acceleration α are as shown in the  figure, determine the n  and  n
                                                                                              x      y
                       components of the velocity and acceleration of P.


                                                                                  n  y
                                                                             P
                                                                       300 mm
                                                           α = 10 rad/sec  2
                                                                         θ = 30°
                                                                                    n
                                                                   ω = 100 rpm       x

                       FIGURE P3.7.1
                       A particle P on the rim of a flywheel.

                       P3.7.2: An automobile A is traveling around a horizontal curve with a radius of 1000 feet.
                       If the maximum radial acceleration is 0.6 g (where g = 32.2 ft/sec ), determine the maxi-
                                                                                 2
                       mum speed V of A.
                       P3.7.3: A pickup truck T travels around a 600-ft-radius curve at 35 mph. If the driver
                       brakes the truck at 5 ft/sec , determine the magnitude of the acceleration a of T. What is
                                               2
                       the angle between a and the direction of travel of T?


                       Section 3.8 Motion in a Plane
                       P3.8.1: See Example 3.8.1, and suppose that for the fixed cam and follower of Figure 3.8.1
                       the following geometric and kinematic data are given:


                                         a  =  150 mm  b  =  100 mm  and θ ˙    =  40 rpm
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