You have a spring with k = 640 N/m connected to a mass with m = 10 kg.  You start the system oscillating and measure the velocity of the mass as it moves through the spring’s equilibrium position to be 4 m/s. At what position is the kinetic energy of the system equal to the potential energy?

A mass attached to a spring is undergoing simple harmonic motion as shown below. The surface is frictionless. The equilibrium position of the spring is indicated by the dashed line. At the point shown, the mass is at its maximum displacement from equilibrium. Which of the following statements is NOT true regarding the point shown? (“The system” refers to the system of the mass and the spring.)

A solid rock, suspended in air by a spring scale, has a measured mass of 9.00 kg. When the rock is submerged in water, the scale reads 4.10 kg. What is the density of the rock? (water density = 1000 kg/m3)  In this problem g=9.8 m/s2

Which description of the motion of a source of sound or listener best fits the graph of frequency vs. time shown?

Water is flowing through the pipe shown below from points 1 to 4. The area of the pipe at point 1 is A1.  The area of the pipe at point 2 is A2.  The area of the pipe at point 3 is A3.  And the area of the pipe at point 4 is A4.  While evaluating the statements below, take A1 = A2 < A3 = A4.  Ignore viscosity and assume that the water fills the pipe completely at all locations. What happens to the pressure from point 3 to point 4? [pressure] In which of the following cases can we not conclude anything definite about the change in pressure? [notsure]

In the 2-tiered pipe shown, the area of the lower pipe is 50 cm2, the absolute pressure in the lower pipe is 400 kPa, and the velocity of the water flowing through the lower pipe is 0.5 m/s. If the height difference between the lower and upper pipe is 12 m and the area of the upper pipe is 10 cm2, what is the absolute water pressure in the upper pipe? Ignore the viscosity of water and assume the water always fills the pipe. (The density of water is 1000 kg/m3.)

A marine engineer is testing a design for the hull of a boat. In order to minimize turbulent drag, she would like to conduct a test in which the flow of fluid around the hull is laminar. From the following table of fluids, which fluid should she choose for the test in order to most likely ensure laminar flow? The boat will move at the same speed in each of the possible fluids.

How much total heat Q must be removed from 1 kg of liquid water at 10°C in order to freeze it?  cw = 4190 J/kg ºC  Lf = 333 kJ/kg

If the pressure in an ideal gas drops to 1/2 the original, what must happen to the volume for the temperature to be the same?

Several oven mitts are made of different materials and have different thicknesses. Which of the following would allow you to hold a hot pan for the longest time? (Assume the area of contact between your hand and the pan is the same in each case.)