This document contains instructions and questions for an engineering mechanics exam. It includes 5 questions related to dynamics concepts like friction, forces, velocities, linear and angular momentum. The first question asks students to calculate the angle a ramp must make with the horizontal for blocks to transfer between conveyor belts without slipping. The second asks for the velocity of a collar sliding on a rod as it passes different points. The third asks for the velocity of a collar striking the end of a rod when acted on by a constant force. The fourth asks students to determine accelerations, tensions in cords and blocks for a system of connected blocks and cords released from rest. The fifth asks students to calculate the linear and angular momentum and kinetic energy of a moving sphere.

1. JIMMA UNIVERSITY, JU
JIMMA INSTITUTE OF TECHNOLOGY, JiT
SCHOOL OF MECHANICAL ENGINEERING
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Re- exam
Course Name: Engineering Mechanics II (Dynamics) Course Code: MEng 1062 Date Nov, 25, 2014
Max. Marks: [50 %] Time Allowed:- 3hrs
Instructions:
o Exam is closed book and using cell phone as calculator or referring to your handout is strictly
forbidden.
o Neat procedure of your work and exact numerical answers attracts marks..
1. In the design of a conveyor-belt system, small metal blocks are discharged with a
velocity of 0.4m/s onto a ramp by the upper conveyer belt shown. If the coefficient of
kinetic friction between the blocks and the ramp is 0.30, calculate the angle θ which
the ramp must make with the horizontal so that the blocks will transfer without
slipping to the lower conveyor belt moving at the speed of 0.14m/s. [10% ]
.
2. The 10-kg collar slides on the smooth vertical rod and has a velocity v1 = 2 m/s in
position A where each spring is stretched 0.1 m. Calculate the velocity v2 of the collar
as it passes point B.[10% ]
Figure 1
Figure 2

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3. The 0.5-kg collar C starts from rest at A and slides with negligible friction on the
fixed rod in the vertical plane. Determine the velocity v with which the collar strikes
end B when acted upon by the 5-N force, which is constant in direction. Neglect the
small dimensions of the collar.
4. The system is released from rest with the cable taut. For block A the friction coefficients are µ 𝑠 =0.2
and µ 𝑘 =0.15. Determine (a) the acceleration of each block (b) tension in the cord and (c) the tension
in each block. [10% ]
5. The 3 kg sphere moves in the X-Y plane and it has the indicated velocity (v) of 6 m/s at a particular
instant. Determine its, (a) Linear momentum, (b) Angular momentum about point O using vector
method and (c) Kinetic energy. [10% ]
Figure 4
Figure 3
Figure 5