# Assignment due in less than 1 hr

1. Nov 14, 2004

### disruptors

Hey ppl, sorry I was just wondering if anyone knew how to do the question i posted earlier(TWO BLOCKS AND TWO PULLEYS), as I have to submit it and cannot figure it out still!?

Thanks...

2. Nov 14, 2004

### tiger_striped_cat

can you post a picture of it. I'm having trouble picturing this system.

3. Nov 14, 2004

### disruptors

here's the pic, thanks

4. Nov 14, 2004

### tiger_striped_cat

where? I dont see it as part of your post

5. Nov 15, 2004

### disruptors

oh sorry tiger, its okay i had to submit it, thx for your time...i cant get the pic up for some reason..

#### Attached Files:

• ###### pulley pic.jpg
File size:
9.8 KB
Views:
76
6. Nov 15, 2004

### disruptors

never mind must have been my browser

7. Nov 15, 2004

### tiger_striped_cat

well how did you do the first part? it looks right to me. you did:

$$\sum{F} = ma$$

always always ALWAYS start with this over and over again (or at least try to strat with this). The right hand side will have only ma or 0 thats all it will ever have ( and zero is a particular case of ma--when it is not accelarating, that is, not moving, or constant velocity) The left hand side just sums your forces. So after picking your postitive and negnative on your x and y axis (always do this too) and drew your free body diagram (I hop you did this) you must of did:

$$T + T = m_2a_2$$

And then you solved for T

Now for the next part do the same thing

1) Draw FBD
2) $$\sum{F} = ma$$
3) $$T - m_1g = m_1a_1$$

And then solve for $$a_1$$ in terms of everything else they gave you