physics
posted by Brianna .
An archer puts a 0.26kg arrow to the bowstring. 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?
m/s
(b) If the arrow is shot straight up, how high does it rise?
m

physics 
Elena
1.
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.
2.
Sometimes I’ve found the answers of this problem based on the following solution
PE =kx²/2 = KE =mv²/2.
This solution gives v =sqrt(k•x²/m) = sqrt(F•x²/x•m) = sqrt(F•x/m) = 32.8 m/s.
And the height from m•g•h =m•v²/2 is
h =v²/2•g = 54.95 m.
But I believe that this solution is incorrect because we have given the magnitude of the average (!) force
So the first solution is quite the thing.
Respond to this Question
Similar Questions

Physics
An archer puts a 0.28 kg arrow to the bow string. An average force of 200 N is exerted to draw the sting back 1.1 m. a) Assuming no frictional loss, what speed does the arrow leave the bow? 
physics
An arrow with a mass of 0.12 kg is pulled back in a bow. After being held still, it is let go, moving at 23m/s after the 0.51meters in which the arrow is in contact with the bow string? 
physics
An archer locks a 0.20kg arrow on a bowstring. Then the archer exerts an average force of 110N to draw the string back 0.60 m . Assume that friction is negligible . What speed does the bow give to the arrow? 
physics
An archer puts a 0.26kg arrow to the bowstring. 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? 
Physics
An archer puts a 0.26kg arrow to the bowstring. 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? 
physics
An archer puts a 0.34 kg arrow to the bowstring. An average force of 213.1 N is exerted to draw the string back 1.48 m. The acceleration of gravity is 9.8 m/s 2 . Assuming no frictional loss, with what speed does the arrow leave the … 
physics
An archer puts a 0.26 kg arrow to the bowstring. An average force of 184.5 N is exerted to draw the string back 1.26 m. The acceleration of gravity is 9.8 m/s 2 . Assuming no frictional loss, with what speed does the arrow leave the … 
physics
An archer puts a 0.39 kg arrow to the bowstring. An average force of 196.3 N is exerted to draw the string back 1.28 m. The acceleration of gravity is 9.8 m/s 2 . Assuming no frictional loss, with what speed does the arrow leave the … 
Physics
a full draw is the maximum distance that an archer can pull an arrow. Using the recurve bow shown below, a particular archer requires an average force of 130N to pull a full draw of 70.0cm. (when the arrow is relaxed in the bow, there … 
Physics
An archer puts a 0.29 kg arrow to the bow string. An average force of 224.8 N is exerted to draw the string back 1.44 m. The acceleration of gravity is 9.8 m/s2 . Assuming no frictional loss, with what speed does the arrow leave the …