Wright State University
Department of Mechanical and Materials Engineering
ME 213, Winter 2011
ME 213 DYNAMICS: MIDTERM EXAM 1
Open Book, Closed Notes, DO NOT write on this sheet, Show all work
Problem 1 (15 points): The motion of a particle is defined by the relation 𝑥 = 15𝑡 3 −
19𝑡 2 + 3𝑡 + 7, where x and t are expressed in meters and seconds, respectively.
Determine the position and the velocity when the acceleration of the particle is equal to
zero.
Problem 2 (30 points): Block B starts from rest and moves downward with a constant
acceleration. Knowing that after slider block A has moved 450 mm its velocity is 5 m/s,
determine the accelerations of A and B, and the velocity of B after 1.2 s.
Problem 3 (40 points): A 22-kg package is at rest on an incline when a force P is applied
to it. Determine the magnitude of P if 8 s is required for the package to travel 6 m up the
incline. The static and kinetic coefficients of friction between the package and the incline
are both equal to 0.25.
Problem 4 (15 points): Rod OA oscillates about O in a horizontal plane. The motion of
the collar of mass m is defined by the relations
𝜋𝑡
𝑟 = 𝑎 + 𝑏 cos ( 2 );
𝜃 = 𝜋(𝑡 2 + 𝑐𝑡)
Determine the radial and transverse components of the force exerted on the collar.