MY NOTES A box slides from rest down a frictionless ramp inclined at 32.0 with respect to the horizontal and is stopped at the bottom of the ramp by a spring with a spring constant of k = 3.50 x 10 N/m. point of release compression of spring If the box has a mass of 12.0 kg and slides 3.00 m from the point of release to the point where it comes to rest against the spring, determine the compression (in m) of the spring when the box comes to rest. Enter a number.cial gravitational potential energy related to the final spring potential energy? Can you write expressions for the initial gravitational potential energy and the final spring potential energy? m Supporting Materials Because it can go from rest to 12.2 m/s (about 27 mi/h) In 1.8 s, one of the fastest-accelerating animals is the cheetah. If Its mass is 56.0 kg, determine the average power developed by the cheetah during the acceleration phase of its motion. Express your answer in the following units. (a) watts Can you write an expression for the average power of the cheetah in terms of the work done by the cheetah and the time over which this work is done? How does the work done by the cheetah compare to its change in kinetic energy? Can you write an expression for the change in kinetic energy of the cheetah in terms of its final and initial speed? W (b) horsepower EX Enter a number. he conversion factor for watts to horsepower? hp Supporting Materials Physical Constants Shoveling snow can be extremely taxing since the arms have such a low efficiency in this activity. Suppose a person shoveling a sidewalk metabolizes food at the rate of 800 W. (The efficiency of a person shoveling is 3%.) (a) What is her useful power output (in W)? 24 W (b) How long (in s) will it take her to lift 2,900 kg of snow 1.20 m? (This could be the amount of heavy snow on 60.0 ft of sidewalk.) What is the relationship between power output, work output and the time needed to do the work? Can you express the power output in terms of the efficiency and the power input? Can you express the work output in term of the change in gravitational potential energy of the snow? s (c) How much waste heat (in J) will she generate in the process? Enter a number. in expression relating the heat generated to the work output? J