Scribd
Upload
30 views2 pages

Chap 4 Tu

The document presents a series of mechanical problems involving angular motion, including the deceleration of pulleys, the velocity and acceleration of points on rotating plates, and the dynamics of oscillating systems. Each problem requires the application of principles of angular velocity, angular acceleration, and kinematics to determine various parameters such as displacement, velocity, and acceleration at specific instances. The problems involve calculations related to harmonic motion, crank mechanisms, and instantaneous centers of velocity.

Uploaded by

Natnael worku
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
30 views2 pages

Chap 4 Tu

The document presents a series of mechanical problems involving angular motion, including the deceleration of pulleys, the velocity and acceleration of points on rotating plates, and the dynamics of oscillating systems. Each problem requires the application of principles of angular velocity, angular acceleration, and kinematics to determine various parameters such as displacement, velocity, and acceleration at specific instances. The problems involve calculations related to harmonic motion, crank mechanisms, and instantaneous centers of velocity.

Uploaded by

Natnael worku
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
You are on page 1/ 2

1. Pulley B is being driven by the motorized pulley A that is rotating at ω A = 20 rad/s.

At time t =
0, the current in the motor is cut off, and friction in the bearings causes the pulleys to coast to a
stop. The angular acceleration of A during the deceleration is αA = −2.5t rad/s2, where t is in
seconds. Assuming that the drive belt does not slip on the pulleys, determine (1) the angular
velocity of B as a function of time; (2) the angular displacement of B during the period of
coasting; and (3) the acceleration of point C on the straight portion of the belt as a function of
time.

2. A circular plate of 120 mm radius is supported by two bearings A and B as shown. The plate
rotates about the rod joining A and B with a constant angular velocity of 26 rad/s. Knowing
that, at the instant considered, the velocity of Point C is directed to the right, determine the
velocity and acceleration of Point E.

3. The punch is operated by a simple harmonic oscillation of the pivoted sector given by θ = θo sin
2πt, where the amplitude is θo = π/12 rad (15o) and the time of one complete oscillation is 1
second. Determine the acceleration of the punch where (a) θ = 0o and (b) θ = π/12
4. Crank CB oscillates about C through a limited arc, causing crank OA to oscillate about O.
When the linkage passes the position shown with CB horizontal and OA vertical, the angular
velocity of CB is 2 rad/s counterclockwise. For this instant, determine the angular velocities of
OA and AB.

5. The crankshaft AB turns with a clockwise angular acceleration of 20 rad/s2. Determine the
acceleration of the piston at the instant AB is in the position shown. At this instant ωAB = 10
rad/s and ωBC = 2.43 rad/s

6. In the position shown in Figure, the angular velocity of bar AB is 2 rad/s clockwise. Calculate the
angular velocities of bars BC and CD for this position

7. Use instantaneous center zero velocity methods for problem 6; determine the angular velocities of bars
BC and CD and the velocity of C using the instant centers for velocities.

You might also like