A3kg chunk of putty moving at a speed of 5 m/a collides with, and sticks to, a 5kg. bowling ball that is initially at rest. the bowling ball and putty are than set in motion of ?
explain i am really confused. i know you have to add or subtract something to m2 because the equation is v2=m1•v1/m2
i think. ? !

You'd have an easier time using the equation if you understood where the equation comes from.

The law here ... the major principle to remember, the key, the fundamental truth, the big cookie ... is the fact that momentum is conserved.  The total momentum after they join up is the same as the total momentum before they meet.

Momentum of an object is (mass) times (speed).

Now, list all the things you know, before and after the putty meets the ball:

Before:  There are two objects.
Mass of putty = 3 kg
Speed of putty =  5m/s
Momentum of putty = 3 x 5 = 15 kg-m/s.

Mass of ball = 5 kg
Speed of ball = zero
Momentum of ball = 5 x 0  =  zero

Total momentum of both things = 15 kg-m/s

After:  There is only one object, because they stuck together.
Mass of (putty+ball) = (3+5) = 8 kg
Speed of (putty+ball) = we don't know; that's what we have to find

Momentum of (putty+ball) = 8 x (speed)



We know that the momentum after is equal to the momentum before.

8 x (speed) = 15 kg-m/s

Divide each side by  8 :

Speed = 15 / 8  =  1.875 m/s   after they stick together.

W= fd
where f is an applied force and d is the distance over which it is applied. when a parachuting skydiver is at constant velocity, he is experiencing "terminal velocity", the point at which his acceleration down is canceled out by air resistance. that means that the resisting force of the air is equal to his weight, but in the opposite direction. with this, we can solve for the work done by the force.
w = fd
w = (92.0)(9.81 m/s^2) (325)
w= 2.93 x 10^5 j
the value for work in this case is positive because it is pushing up on the skydiver, who has a downward force of gravity.
therefore the answer is 2.93 x 10^5 j