Concept explainers
(a)
The impact speed when the hammer hits the test specimen.
Answer to Problem 17.137RP
The impact speed when the hammer hits the test specimen is
Explanation of Solution
Given information:
Initial energy of the system is calculated as follows:
Final energy of the system is calculated as follows:
Apply the conservation of energy as follows:
The impact speed when the hammer hits the test specimen is calculated as follows:
Thus, the impact speed when the hammer hits the test specimen is
Conclusion:
The impact speed when the hammer hits the test specimen is
(b)
Find the force on the pin O
Answer to Problem 17.137RP
Force at the point O before impact is
Explanation of Solution
Moment of inertia about “O” is calculated as follows:
Free body diagram of the system is shown below:
Applying newtons second law in rotation as follows:
Center of gravity of whole system is calculated as follows:
Apply Newton’s second law of motion before impact in horizontal direction as follows:
Apply Newton’s second law of motion before impact in vertical direction as follows:
Force at the point O before impact is calculated as follows:
Thus, Force at the point O before impact is
(c)
The amount of energy that test specimen absorb.
Answer to Problem 17.137RP
Amount of energy that test specimen absorb is
Explanation of Solution
Initial energy of the system is
Final energy of the system is calculated as follows:
Amount of energy that test specimen absorb is calculated as follows:
Thus, amount of energy that test specimen absorb is
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Chapter 17 Solutions
Vector Mechanics For Engineers
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