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Extra Credit (Maximum 5 points)What is one thing you learned in this class that you did not know and found interesting? Explain your answer. You must write at least 5 sentences for full credit.

The figure shows a uniform, horizontal beam (length = 10 m, mass = 35 kg) that is pivoted at the wall, with its far end supported by a cable that makes an angle of 51° with the horizontal. If a person (mass = 80 kg) stands 3.0 m from the pivot, what is the tension (in N) in the cable?

What causes cancer in cells?

A particle located at the position vector r= (i+2j) m has a force F= (2i+3j) N acting on it. Find the torque (in N*m) about the origin.

Ten girls, of mass m=35kg each, initially stand at different points on the rim of a merry-go-round (essentially a disk that spins).  The merry-go-round has a moment of inertia of 800 kgm^2 and a radius of 4.0m.  The merry-go-round has an initial angular velocity of 0.20 rad/s and rotates freely on frictionless bearings.  On a signal the girls all start to move toward the center of the merry-go-round until they reach a distance of 1.5m from the center, where they stand again.  Find the new angular velocity of the system (in rad/sec).

A wheel spinning on an axis through its center has a constant angular acceleration of 3.5 rad/s^2.  Assuming the wheel starts from rest, through what angle (in rad) must the wheel turn for the angular velocity to reach 140 rad/s?

The figure shows a uniform, horizontal beam (length = 10 m, mass = 35 kg) that is pivoted at the wall, with its far end supported by a cable that makes an angle of 51° with the horizontal. If a person (mass = 80 kg) stands 3.0 m from the pivot, what is the tension in the cable?

A wheel (radius = 0.40 m) starts from rest and rotates with a constant angular acceleration of 2.0 rad/s2. At the instant when the angular velocity is equal to 1.2 rad/s, what is the magnitude of the total linear acceleration (in m/s^2) of a point on the rim of the wheel?

Ten girls, of mass m=35kg each, initially stand at different points on the rim of a merry-go-round (essentially a disk that spins).  The merry-go-round has a moment of inertia of 800 kgm^2 and a radius of 4.0m.  The merry-go-round has an initial angular velocity of 0.20 rad/s and rotates freely on frictionless bearings.  On a signal the girls all start to move toward the center of the merry-go-round until they reach a distance of 1.5m from the center, where they stand again.  Find the new angular velocity of the system (in rad/sec).

Which of the following interventions targets a population at risk for a particular disease or condition?