Interesting, everyone is correct with a few exceptions. In the

original problem knowing the force used to hit the puck is not enough.

You need to know either the distance or the time over which the force

was applied to determine the initial speed of the puck or you need to

know the initial speed. Tony had the most efficient solution if you

knew the energy applied by hitting the puck.

Maginsta's mistakes seem purposeful but may just signify an

ignorance of mathematics: "Sin Force = mass * acceleration, and

constancy would define acceleration as 0, how can a force exist?" I

would assume that "Sin" is a typo and should read "Since" but

mathematics is the language of physics and in mathematics "Sin" is a

trigonometric function. In "Absent acceleration, how do you derive a

force as being a constant?" no acceleration means no force and derive

is a calculus term meaning a rate of change and if the rate of change

is constant then it is changing constantly. However, impulses usually

involve a changing force in which case you need to know the rate at

which it is changing or the average force otherwise knowing the

distance or time in which it is changing will not give you the energy

imparted to the puck.

Mr. Watland's mistake involved "(i) Impulse = (Driving Force) *

(Time of Application of Force)". Looking at the units; impulse has

units of momentum or length squared divided by time squared while

force (mass multiplied by length divided by time squared) multiplied

by time has units of mass times length divided by time. They are not

equal.