John(body mass=160pounds) is taking off for a long jump. the average ground reaction force fg at takeoff is 1400 n pointing forward at an angle of 35° above the horizontal. (a) draw a free body diagram of the person, specifying ground reaction forces fg, y and fg, x.
(b)calculate ground reaction forces f g, y and fg, x.
(c)what is the acceleration ax?
(d) what is the acceleration ay?

The free body diagram of John is shown in the attached figure (in the FBD john's mass is supposed to be concentrated at his center of mass and FBD is made of center of mass)

b) As shown in the FBD the ground reaction forces are:

i) In X direction

ii) In Y direction

c) The respective accelerations in x and y direction's is calculated by newton's second law as indicated under

! 55 !  

write a paragraph or story to explain the transformation between potential and kinetic energy as shown in your picture or model.  

you should have at least 5 complete sentences with a main idea and supporting details.  

you must include the following words:  

potential energy

kinetic energy

mechanical energy

conservation of energy

dude, this is hard lol : ))