Newton's Second Law for a Single Force

[djester555]

Homework Statement

Stopping a Salmon The tension at which a fishing line snaps is commonly called the line's "strength." What minimum strength is needed for a line that is to stop a salmon of weight 85 N in 11.6 cm if the fish is initially drifting at 3.0 m/s? Assume a constant acceleration.

Homework Equations

X1= -0
X2= .116
V1 = 3.0
V2= 0
A = unknown
T = unknown
T =

The Attempt at a Solution

Solved for A and found it to be -38.7931

m = 85 / 9.8


F = ma
F= (8.673)(-38.793)
F = - 336.45
Not sure what i did wrong

 

[rl.bhat]

Fishing line may not be in the direction of drift velocity of salmon.

 

[djester555]

so that would swithch the sign to positive then