Concept explainers
(a)
To Calculate:
The horizental component of
(a)
Answer to Problem 74P
Explanation of Solution
Given data:
Mass of the ball is
Formula Used:
Angular momentum:
Where,
Newton’s second law of motion:
Where, m is the mass and a is the acceleration.
Calculation:
By the expression of the angular momentum of the ball about the point of support as
Then, by applying Newton’s second law to the ball to get
And
Now, eliminate
By substituting the
Then solve for the velocity of the ball
Substitute numerical values to get
Express the position vector of the ball as
Find the velocity of the ball:
Evaluate for
Substitute for
Substitute into equation
Therefore, the horizontal component of angular momentum
And the vertical component of angular momentum
Conclusion:
(b)
To Calculate:The magnitude of the torque exerted by gravity about the point of support.
(b)
Answer to Problem 74P
Explanation of Solution
Given data:
From the previous part:
Formula Used:
The magnitude of the torque exerted by gravity about the point of support as
Calculation:
By differentiating the angular momentum:
Therefore, the magnitude of above derivative
Substitute the values:
Conclusion:
Torque exerted by gravity about the point of support is
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Chapter 10 Solutions
Physics for Scientists and Engineers, Vol. 3
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