posted by Haley on .
An archer puts a 0.26-kg arrow to the bow-string. An average force of 200 N is exerted to draw the string back 1.4 m.
(a) Assuming no frictional loss, with what speed does the arrow leave the bow?
(b) If the arrow is shot straight up, how high does it rise?
I got 47 for A
and 113 for B, but neither work?
W =F•x =200•1.4 =280 J,
W =KE = m•v²/2,
v =sqrt(2•W/m) = sqrt(2•280/0.26) =46.4 m/s.
KE =PE = m•g•h
h = KE/m•g = 280/0.26•9.8 ≈110 m.
both of these answers
These answers (v=46.4 m/s, h= 109.89≈110 m) are correct.