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A person drops a cylindrical steel bar (Y = 1.70 x 1011 Pa) from a height of 1.30 m (distance between the floor and the bottom of the vertically oriented bar).  The bar, or length L = 0.63 m, radius R =0.55 cm, and mass m=1.30 kg, hits the floow and bounces up, maintaining its vertical orientation.  Assuming the collision is elastic (bounces) and no rotation occurs, what is the maximum compression of the bar?  The formula for stress is given by:

You spray your sister with water from a garden hose. The water is supplied to the hose at a rate of 0.111 liters per second and the diameter of the nozzle you hold is 5.79 mm. At what speed does the water exit the nozzle?

Which is true about elastic collisions:

A straightforward method of finding the density of an object is to measure its mass and then measure its volume by submerging it in a graduated cylinder. What is the density of a 240-g rock that displaces 89.0 mL of water?

What is the absolute pressure at a depth of 9.73 m below the surface of a deep lake?  Take 1.01 x 105 Pa as atmospheric pressure.

A force of 300 N is applied 20 cm from the pivot point at an angle of 30o.  What is the torque?

For which case will the flow rate increase for Poiseuille flow?

After an average acceleration of 3.39 m/s2 during 2.29 s, a car reaches a final velocity of 16.1 m/s.  Find the car’s initial velocity.

A 129-kg horizontal platform is a uniform disk of radius 1.61 m and can rotate about the vertical axis through its center. A 65.7-kg person stands on the platform at a distance of 1.07 m from the center and a 27.3-kg dog sits on the platform near the person, 1.31 m from the center. Find the moment of inertia of this system, consisting of the platform and its population, with respect to the axis.

Vector A has magnitude of 13.5 and is 345o counter-clockwise up from the +x-axis.  What are the x- and y-components of the vector?