guy who answered before will get 10 pts when i can give it
this one seems simple but again i am getting 2.94 m/s^2 while the ANSWER is 2.16 m/s^2
It states calculate the acceleration....It is a 3 kg block on a table attached by pulley to a 2kg block that is hanging off the side of the table. The coefficient of friction is .3
neglect the friction of the pulley
2006-10-29 06:19:19 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Physics
First, identify the two forces you are dealing with. Frictional force (F1) and and the force of a falling object (F2).
Now lets calculate each.
F1=m g mu where m=mass, g= gravity, and mu=coff. fric.I look at it like some rail road cars. (This is a little sadistic,
F1=3*9.81*.3=8.829
F2=m g = 2*9.81=19.62 (remember the falling object is the 2kg block).
The total Force= F2-F1. Then to find acceleration we need to use F=ma.
Once again. The main problem here is conceptualizing the problem and how these forces relate. This may take a bit of thinking about the problem, but realize that the two masses are directly connected and the mass for the total Force is block 1 +block 2. Thus a=(F2-F1)/(m1+m2)= (19.62-8.829) N/(3+2)Kg = 2.158m/s^s.
I think the most difficult part is understanding that for the total force you actually need to consider both masses even though only one is generating the movement. (This sounds a little sadistic but gets the point across well) Lets say that you were lying on your back and those two boxes started sliding off a shelf and hit you. If only one hit you a much smaller force would be impacted on you than if they both hit you. The force of those to boxes hitting you is the same force we are calculating in this problem.
2006-10-29 06:56:42 · answer #1 · answered by Anonymous · 1⤊ 0⤋
Physics is better been taught with drawings. If you know how to draw the problem, you will know how to approach the solution.
2006-10-29 14:45:09 · answer #2 · answered by The young Merlin 4 · 0⤊ 1⤋
F = 9.8*(2 - 0.3*3) = ma
a =9.8(2-0.9)/5
2006-10-29 14:25:18 · answer #3 · answered by Helmut 7 · 1⤊ 0⤋
Is there a math error somewhere?
f_drag = m1*g*mu
f_pull = m2*g
accel = (f_pull - f_drag)/(m1+m2)
2006-10-29 14:24:06 · answer #4 · answered by arbiter007 6 · 0⤊ 1⤋
it is 2.16m/s^s cause when u had multiply and divide the answer thats what i got.
Goodluck!
2006-10-29 14:22:42 · answer #5 · answered by Trina 2 · 0⤊ 1⤋