Concept explainers
Lineman A has a mass of 100 kg and is traveling with a velocity of 4 m/s when he collides head-on with lineman B, who has a mass of 90 kg and is traveling at 4.5 m/s. If both players remain on their feet, what will happen? (Answer: Lineman B will push lineman A backward with a velocity of 0.03 m/s.)
To determine: The kinetic energy of lineman A.
Answer to Problem 6IP
The kinetic energy of lineman A is
Explanation of Solution
Calculation:
Write an expression to find the kinetic energy of lineman A.
Here,
Substitute 100 kg for
Therefore, the kinetic energy of lineman A is
Therefore, the kinetic energy of lineman A is
To determine: The kinetic energy of lineman B.
Answer to Problem 6IP
The kinetic energy of lineman B is
Explanation of Solution
Calculation:
Write an expression to find the kinetic energy of lineman B.
Here,
Substitute 90 kg for
Therefore, the kinetic energy of lineman B is
Therefore, the kinetic energy of lineman B is
To determine: The final velocity of combined mass.
Answer to Problem 6IP
Therefore, the kinetic energy of lineman B is higher than lineman A, thus lineman B will push lineman A backward with a magnitude of velocity
Explanation of Solution
Calculation:
Write an expression of conservation of linear momentum to find the final velocity of combined mass.
Here,
Substitute 100 kg for
Therefore, the velocity of the combined mass is
Therefore, the kinetic energy of lineman B is higher than lineman A, thus, lineman B will push lineman A backward with a magnitude of velocity
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Chapter 12 Solutions
BASIC BIOMECHANICS
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