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Two sound waves are traveling through the same medium. They have the same amplitude, wavelength, and direction of travel. If the phase difference between them is 5π, the type of interference they exhibit is:

Suppose the coefficient of static friction between the road and the tires on a car is 0.4 and the car has no negative lift. What speed will put the car on the verge of sliding as it rounds a level curve of 50.0 m radius?

A flywheel with a diameter of 1.23 m is rotating at an angular speed of 150 rev/min. What is the linear speed (in m/s) of a point on the rim of the flywheel? 

A horizontal vinyl record of mass 0.0522 kg and radius 0.0932 m rotates freely about a vertical axis through its center with an angular speed of 5.71 rad/s and a rotational inertia of 2.02 x 10-4 kg·m2. Putty of mass 0.0189 kg drops vertically onto the record from above and sticks to the edge of the record.What is the angular speed of the record immediately afterwards?

A person pushes a 48.5kg block of ice  at an angle 30.80 below the horizon across a lake as shown in the figure.   Calculate the minimum force F (in N) he must exert to get the block moving. (Hint: Horizontal component of force = Static friction force) (The coefficient of static friction is 0.1 and the coefficient of kinetic friction is 0.03)

Find the escape speed on a spherical asteroid whose radius is 927 km and whose gravitational acceleration at the surface is 0.958 m/s2.  Then calculate how far  (in km) from the surface will a particle go if it leaves the asteroid’s surface with a radial speed of 877 m/s? (Enter the distance in km.)

A puck of mass m = 1.60 kg slides in a circle of radius r = 18.0 cm on a frictionless table while attached to a hanging cylinder of mass M = 4.0 kg by a cord through a hole in the table. What speed keeps the cylinder at rest?

A  spring stretches 4.68 cm vertically when a 3.50 kg object is suspended from it.  Find the distance (in cm) the spring stretches if you replace the 3.50 kg object with a 4.40 kg object. Assume that the spring obeys the Hook’s law.

During spring semester at MIT, residents of the parallel buildings of the East Campus dorms battle one another with large catapults that are made with surgical hose mounted on a window frame. A balloon filled with dyed water is placed in a pouch attached to the hose, which is then stretched through the width of the room. Assume that the stretching of the hose obeys Hooke’s law with a spring constant of 150 N/m. If the hose is stretched by 3.90 m and then released, how much work does the force from the hose do on the balloon in the pouch by the time the hose reaches its relaxed length?

A puck of mass m = 1.60 kg slides in a circle of radius r = 18.0 cm on a frictionless table while attached to a hanging cylinder of mass M = 8.0 kg by a cord through a hole in the table. What speed keeps the cylinder at rest?