Concept explainers
The correct statement.
Explanation of Solution
Given:
Mass of two cylinders is not equal and pulley is frictionless.
Formula used:
Write the expression for kinetic energy.
Here,
Write the expression for the change in the kinetic energy of the system.
Since the system is released from rest initial speed of the system is zero.
Substitute
Therefore,
Write the expression for potential energy.
Here,
Write the expression for the change in the potential energy of the system.
Here,
Consider
Conclusion:
Since the change in potential energy is less than zero and change in kinetic energy is greater than zero. Thus, option (a) is correct.
Since the height of the system is changing so change in potential energy cannot be zero. Thus, option (b) is incorrect.
The system is moving downwards with some speed so the change in kinetic energy cannot be zero. Thus, option (c) is incorrect.
Since option (b) and (c) are incorrect. Thus, option (d) is incorrect.
Change in kinetic energy could not be less than zero. Thus, option (e) is incorrect.
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Chapter 7 Solutions
Physics for Scientists and Engineers
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