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The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

What’s #16 asking and how do i solve it?

Which of the following is a true statement about the acceleration ~a of the pendulum bob ~a is equal to the acceleration due to gravity. ~a is perpendicular to the bob’s trajectory. ~a is equal to the instantaneous rate of change in velocity. ~a is tangent to the bob’s trajectory.