- #1

cupcaked

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## Homework Statement

okay this is probably extremely basic stuff but I'm having a lot of trouble in this class and i hope someone can help! :/

A 10 kg mass is placed on a fricitonless surface and is attached to a 5 kg mass as shown by a light and inextensible string.

( here is a drawing of the model: http://i53.tinypic.com/ekne6e.png )

a) Find the acceleration with which the system moves.

b) What is the speed of the masses when the 5 kg mass strikes the floor?

c) After the 5 kg mass strikes the floor, the 10 kg mass on the table continues to move to the right. How far from the edge of the table does it land?

d) How would your answer to part c change if there was friction between the mass and the table? Explain.

## Homework Equations

## The Attempt at a Solution

a) I set up the equations:

T = 10a

49-T = 5a

49-10a = 5a

so i got a = 3.266 m/s^2

b) I used the formula Vf^2 = Vi^2+2ad but I've got a feeling I'm approaching this problem totally wrong. But anyway:

Vf^2 = (3.266^2)+(2*9.8*0.6)

Vf^2 = 22.43

Vf = 4.74 m/s^2 (i put that as my answer)

c) I have no clue how to approach this, if anyone can guide me please? All I can think of is using the same equation as the last part but I don't think I'm right?

d) I put: If the surface had friction, the answer to part (c) would be less than the answer obtained in part (c), because the friction would be an opposing force against where the mass is trying to move.

Not the best explanation but it answers the question, I think.

if anyone can help I would appreciate it SO much! I'm currently failing ap physics and I really don't want to be :'(