Figure P8.45

. Calculate the potential energy of a 75 Kg boulder sitting at the edge of a cliff that is 210 meters from the ground (yf=0). b. If the boulder is suddenly pushed over the side of the cliff what is the velocity of the boulder when it is 50 meters from the ground?

For its size, the common flea is one of the most accomplished jumpers in the animal world. A 2.10-mmmm-long, 0.470 mgmg flea can reach a height of 20.0 cmcm in a single leap.     Part A Ignoring air drag, what is the takeoff speed of such a flea? Express your answer in meters per second. Part B Calculate the kinetic energy of this flea at takeoff. Express your answer in joules. Part C Calculate the kinetic energy per kilogram of mass. Express your answer in joules per kilogram. If a 77.0 kgkg, 2.00-mm-tall human could jump to the same height compared with his length as the flea jumps compared with its length, how high could the human jump? Express your answer in meters. If a 77.0 kgkg, 2.00-mm-tall human could jump to the same height compared with his length as the flea jumps compared with its length, what takeoff speed would the person need? Express your answer in meters per second. Most humans can jump no more than 60.0 cmcm from a crouched…

A crate with mass m = 33.3 kg being pushed up an incline that makes an angle φ = 22.7 degrees with horizontal. The pushing force is horizontal, with magnitude P, and the coefficient of kinetic friction between the crate and the incline is μ = 0.358. Consider the work done on the crate as it moves a distance d = 5.32 m at constant speed. a. What is work done by the pushing force, in joules?  b. What is the work done by friction, in joules?  c. What is the work done by gravity, in joules?  d. What is the net work, in joules?

Releasing some frustration at the end of the semester, you throw your physics book (mass of 2.7 kg) off of a 25 m tall building. You throw your book so that it has a speed of 6 m/s right after you let go. What is the kinetic energy of your book after you let go? (in J) 16.2 130. 0 48.6 662 How how fast is your textbook moving right before it lands? For now, ignore friction. (in m/s) 28.1 22.9 21.3 16.7

= 13 kg, and m3 20 kg, respectively, are attached by strings over frictionless pulleys as indicated in the figure below. The horizontal surface 3.4 kg, m2 %3D Three objects with masses m, exerts a force of friction of 30 N on m,. If the system is released from rest, use energy concepts to find the speed of m, after it moves down 4.0 m. m/s m2 m1 m3

Please atleast answer this question

Justin, with a mass of 50 kg, is going down an 8.0-m-high water slide. He starts at rest, and his speed at the bottom is 12 m/s. How much thermal energy is created by friction during his descent? Express your answer with the appropriate units. Eth = μA Value Units ?

M PAMP7 ** F20 A student pulls a crate of mass M up the inclined surface the distance d. The surface rises 0 degrees above the horizontal, as shown in the figure How much work does gravity do on the crate? Please use the following values: M = 11.9 kg, 0 = 26.9°, d = 5.88 m, g 9.80 m/s (PAMP716F20) a) 0612 J b) О310J c) O-612 J d) 0 686 J e) O-310 J

Calculate the potential energy, kinetic energy, mechanical energv, velocitv, and height of the coaster at the various locations. No Friction on this Roller Coaster. mass of the roaller coaster car = 85 kg 100 start 95 Let gravity on Earth equal 10 m/s? Bcar bumper D E water F finish A B D E P.E. К.Е. M.E. 5 m/s speed height 80 m Height in meters