Two objects of masses m, = 0.56 kg and m, = 0.88 kg are placed on a horizontal frictionless surface and a тg т compressed spring of force constant k = 280 N/m is placed between them as in Figure P6.28a. Neglect the mass of the spring. The spring is not attached to either object and is compressed a distance of 9.8 cm. If the objects are released from rest, find the final veloc- ity of each object as shown in Figure P6.28b. т m2 Figure P6.28

Leah is competing in the national diving championships.  She has a mass of 67 kg and leaves the springboard from a height of 2.9 meters above the water surface with a speed of 5.83 m/s in the upward direction. a) Determine Leah’s speed in m/s when she strikes the water. b) Leah’s body plunges to a depth of 2.12 meters below the water surface before coming to a stop.  Determine the magnitude of the average force of water resistance in Newtons experienced by her body

A 70 kg stunt- woman falls off a bridge and travels 29.0 before colliding with a pile of mattresses. The mattresses are compressed 1.00 m before she is brought to rest.  Calculate the magnitude of the average force exerted by the mattresses on the stunt-woman.

Gayle runs at a speed of 4.35 m/s and dives on a sled, initially at rest on the top of a frictionless snow-covered hill. After she has descended a vertical distance of 5.00 m, her brother, who is initially at rest, hops on her back and together they continue down the hill. What is their speed at the bottom of the hill if the total vertical drop is 15.0 m? Gayle's mass is 49.5 kg, the sled has a mass of 5.25 kg and her brother has a mass of 30.0 kg. m/s Need Help?

A spring with a force constant of 12 N/m rests horizontally on a table and projects balls with a mass of 8.3 × 10-3 kg towards targets placed on the ground 93 cm below. If the spring is compressed by 4.0 cm, how far does the ball travel horizontally before it hits the ground?

A 0.203 kg baseball is pitched to a batter with an initial speed of 18.4 m/s, if the bat delivers a force of 2.09E3 N for a time of 0.00300 s, what speed does the baseball have as it is hit back towards the pitcher?

Two forces, F :(-4.00î – 3.95ĵ) N and F, = (-3.95î – 4.95j) N, act on a particle of mass 1.90 kg that is initially at rest at 1 coordinates (+1.95 m, +4.05 m). (a) What are the components of the particle's velocity at t = 11.1 s? m/s (b) In what direction is the particle moving at t = 11.1 s? ° counterclockwise from the +x-axis (c) What displacement does the particle undergo during the first 11.1 s? (d) What are the coordinates of the particle at t = 11.1 s? X = m y =

A 61.0-kg athlete leaps straight up into the air from a trampoline with an initial speed of 9.7 m/s. The goal of this problem is to find the maximum height she attains and her speed at half maximum height. (a) What are the.interacting.objects and how.do.they.interact? This answer has not been graded yet (b) Select the height at which the athlete's speed is 9.7 m/s as y = 0. What is her kinetic energy at this point? What is the gravitational potential energy associated with the athlete? (c) What is her kinetic energy at maximum height? What is the gravitational potential energy associated with the athlete? (d) Write a general equation for energy conservation in this case and solve for the maximum height. Substitute and obtain a numerical answer. m (e) Write the general equation for energy conservation and solve for the velocity at half the maximum height. Substitute and obtain a numerical answer. m/s