An archer puts a 0.34 kg arrow to the bowstring. An average force of 220 N is exerted to draw the string back 1.3 m. Assume that air resistance is negligible. If the arrow is shot straight up, how high does it rise?

Question

I am confused at how to find the distance that it will rise.

drwls · Answer

The work done drawing the bow is
W = (average force)*(distance pulled)
= 286 Joules

Set that equal to the potential energy gained at highest altitude, H

M g H = 286 J

H = 286/(0.34*9.8) = ____?

Note that kinetic energy does not enter into the equation at highest altitude because the arrow is temporarily motionless there.

bob · Answer

Two girls with masses of 50.0 kg and 70.0 kg are at rest on frictionless in-line skates. the larger girl pushes the smaller girl so that the latter rolls away at a speed of 10.0 m/s. What is the effect of the action on the larger girl? What is the impulse that each girl exerts on the other?

Anonymous · Answer

dunno