Physics 220 A Final Examination                                                                Dec. 11, 2003

Name

  1. The concord airplane travels at about 2300km/h. it take

(a)  2.5s

             to travel 1.0 mile.

  1.   A space vehicle accelerates uniformly from 65m/s at t = 0 to 162m/s at t = 10.0s. Between t = 2.0s and t = 6.0s it moves

(b) 4.2 x 102 m

  1. A projectile is fired with an initial speed of 51.2m/s at the angle of 44.5º above the horizontal on a long flat firing range. The total time in the air is

(b) 7.32s

  1. Three blocks on a frictionless horizontal surface are in contact with each other as shown. If m1 = m2 = m3 = 12.0kg and F = 96.0N, the force of contact on m2 from m1 is

(b) 32.0N.

  1. In the figure the coefficient of static friction between mass m1 and the table is 0.40, whereas the coefficient of kinetic friction is 0.30. To keep the system moving at constant speed the value of m1 will be

(b) 6.7kg.

  1. The effective value of g, the acceleration of gravity, at 3200km above the Earth’s surface is (Assume the Earth’s average radius is

(c) 4.36 m/s2.  

  1. A 1200-kg car rolling on a horizontal surface has speed v = 60km/h when it strikes a horizontal coiled spring and is brought to rest in a distance of 2.2m. The spring constant of the spring is 

(c) 6.9 x 104N/m.

  1. A 145-g baseball is dropped from a tree 12.0m above the ground. It hits the ground with speed of 8.00m/s. The average force of air resistance exerted on the baseball is

(a)–1.03N.

  1. An explosion breaks an object into two pieces, one of which has 1.5times the mass of the other. If 17,500J were released in the explosion, the kinetic energy acquired by the lighter piece is

(b) 10,500J.

  1. A uniform ball of mass M and radius R1 on the end of a thin massless rod is rotated in a horizontal circle of radius R0 about an axis of rotation AB, as shown. The moment of inertia of the ball about AB is

                  (c) (2MR12/5) + MR02.

  1. A uniform 1.0-m-long stick with a total mass of 300g is pivoted at its center. A 3.0-g bullet is shot through the stick midway between the pivot and one end (as shown in Figure). The bullet approaches at 250m/s and leaves at 160m/s. After the collision the stick is spinning with an angular speed of

(c)  2.7rad/s.

  1. The tension FT in the wire that supports the 30.0-kg beam shown in Fig. is

(c) 2.3 x 102 N.