What force is needed to give a 0.25-kg arrow an acceleration of 196 m/s squared?

1 Answer
Nov 4, 2017

#F=49"N"#

Explanation:

We can apply Newton's second law here, which in summary states that the acceleration underwent by an object is directly proportional to--and in the same direction as--the net force experienced by the object.

We know this as the familiar equation: #color(blue)(vecF=mveca)#.

Given:

  • #m=0.25"kg"#
  • #a=196"m"//"s"^2#

With this information we can calculate the force required to cause the given acceleration with the given mass constraint.

Note that I am assuming that this arrow is shot horizontally, where the applied force--and consequently the given acceleration of the arrow--is entirely in the x-direction. I also make the usual assumptions for projectile motion at this level: air resistance is negligible, ignore the curvature of the earth, etc.

Of course the arrow also undergoes a vertical acceleration equal to #-g#, or the free-fall acceleration, so again, I assume the desired acceleration is meant to be entirely horizontal and otherwise unaffected by the force of gravity.

Then:

#F=ma#

#=>=(0.25"kg")(196"m"//"s"^2)#

#=>=color(blue)(49"N")#