Concept explainers
(a)
The acceleration of the center of mass of the spherical shell
(a)
Answer to Problem 90P
Explanation of Solution
Given:
The coefficient of static friction =
Angle of inclination =
Formula used:
Torque is defined as,
F is the applied force on the object and r is the position vector from axis of rotation to the applied force
Acceleration of the object in terms of
Here I is the moment of inertia and
Calculation:
Consider the static friction on the shell is
Torque on the shell by static friction,
Now, by second law of motion for rotation:
Net force along the x axis,
By second law of motion
Conclusion:
The center of mass of the spherical shell is
(b)
The frictional force acting on the ball
(b)
Answer to Problem 90P
The frictional force acting on the ball is
Explanation of Solution
Given:
From part a),
Expression for the frictional force,
Acceleration of the center of mass of the spherical shell,
Calculation:
Since expression of the static friction,
Substitute the values:
Conclusion:
The static friction on the shell is
(c)
The maximum angle of the inclination for which the ball rolls without slipping
(c)
Answer to Problem 90P
Explanation of Solution
Given:
From part a),
Expression for the frictional force,
Acceleration of the center of mass of the spherical shell,
Calculation:
Net force along the y axis,
Since, there is no any acceleration along the y axis, so,
Maximum static friction,
Now, torque on the shell,
By 2nd law of motion for rotation, we get,
Now, net force along the x axis,
Now, by 2nd law of motion, we get,
Now, let’s plug the value of
At the maximum acceleration,
Conclusion:
The maximum angle is
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Chapter 9 Solutions
Physics for Scientists and Engineers
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