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Ellywick decides to try to move through a forest by brachiation, swinging below a handhold to move forward to the next handhold. Weighing 40 kg, Ellywick has an arm length (hand to shoulder) of 0.60 m. We can model her motion as that of a point mass swinging at the end of a 0.60-m-long, massless rod. At the lowest point of her swing, Ellywick is moving at 2.9 m/s. What upward force must a branch provide to support the swinging Ellywick? 

Glim starts walking to the right along a precariously positioned beam. The 45 kg, 5.0-m-long beam is supported by, but not attached to, two poles placed underneath the beam. The first pole is at the left end, and the second pole is 3 m to the right of the first one. Once Glim gets 1.6 m from the right end of the beam, it starts to tip over. What is Glim’s mass?

Blood vessels are found in epithelial tissue, but epithelium is not supplied by nerve fibers.

Two planets, Fibblestib and Dimble, orbit a single star. The gravitational force from the star on planet Fibblestib is two times the force from the star on planet Dimble. Also, planet Dimble has three times the mass of planet Fibblestib. What is the ratio of the two planets’ orbital radii RFibblestib/RDimble?

The function of Transverse tubules is to conduct electrical impulses from the surface of the cell down into the sarcoplasmic reticulum in the cell.

Carlin hangs a sign in front of her shop with a cable held away from the building by a lightweight pole. The cable makes an angle of 60 degrees with the wall, and the sign hangs from the edge of the pole, which has a length of 1.5 m and is perpendicular to the wall. Once the sign is set up, Carlin measures a tension in the cable of 150 N. What is the mass of the sign?

Dalaba swings a small block of mass M = 5.0 kg in a horizontal, circular path on a frictionless surface from a spring. One end of the spring is fixed to the center of the circle and the other end is fixed to the block. The relaxed length of the spring is 25 cm, which then stretches to a total length of R = 30 cm during the circular motion. If Dalaba measures an angular speed of 3.5 rad/s, what is the spring constant for the spring k?

Bilbrun observes his windmill rotate with constant angular speed 6 times in five minutes. Then the wind dies down, and the windmill rotates exactly 3 more times before coming to rest. What is the magnitude of the average angular acceleration of the windmill after it begins slowing down?

Unvera is operating an apparatus containing a flywheel, which accelerates from rest to its maximum angular speed of 25 rpm, turning through 80 revolutions in the process. How long does Unvera’s flywheel take to accelerate to its maximum speed?

Orryn sets up a mass and pulley system, as shown in the figure. A string is wrapped around a non-uniform pulley of radius 10 cm, which can rotate freely about its center axis. The loose end of the string is attached to a block. The block and pulley each have mass 4.5 kg. If Orryn observes the block accelerate downwards at a rate of 5.5 m/s2, what is the moment of inertia of the pulley?