Wednesday

January 28, 2015

January 28, 2015

Posted by **Isis** on Wednesday, January 30, 2013 at 5:50pm.

a) what is the initial kinetic energy of the ball?

b) what is the final kinetic of the ball?

c) what is the final velocity of the ball?

2.)A boy is doing chin-up. If the boy does 450 N of work to lift his body 0.25 m.

a) how much work does the boy do to lift himself up?

b) if he starts from rest, what his final kinetic energy?

c) what is the boy's final velocity?

>> FORMULAS <<

W= Fd

KE=1/2 v^2

PE= mgm

kg.m/s^2.m

kg.m^2/s^2=J

im sorry i don't know which formula to use. please help me! :)

- Physics ~Work Kinetic Energy~ -
**Elena**, Wednesday, January 30, 2013 at 6:15pma) KE₀=0

b) KE= 300 J

c) v=sqrt(2•KE/m)=…(m/s)

2)

a)W=mgh=450•0.25 = ... J

b) KE(fin) =0

c) v=0

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