# Just a little pulley problem

• Differentiate it

#### Differentiate it

Homework Statement
Could someone help me out with this?
Relevant Equations
-

Homework Statement:: Could someone help me out with this?
Relevant Equations:: -

View attachment 314286
Yes, someone can, but we need to see your attempt at solving this before we can begin to help.

topsquark
Yes, someone can, but we need to see your attempt at solving this before we can begin to help.
Well I used the Net work done by a massless string thing and i seem to be getting 1.2 m/s instead of the 1.8 m/s shown in the answer key

it helps to be very methodical with such questions.
Define variables for the lengths of string of interest. There's the string running from the large pulley to the rightmost pulley, the string from the centre if the large pulley to the other small pulley, the string running from the bottom of the large pulley to the bottom of that same small pulley, and the vertical string.
What fact relates those four lengths?
What fact relates the first two?
What fact relates the second and third?

Well I used the Net work done by a massless string thing and i seem to be getting 1.2 m/s instead of the 1.8 m/s shown in the answer key
That isn't much information regarding the specifics or your attempt. Rather than ask about how you used and obtained the Net work of the massless string, I'll ask some questions regarding the objects shown in the figure.

It looks like the two small pulleys are fixed in position relative to the bench/table. Is that correct?

Is the axel of the large pulley a fixed distance from block A ?

Is the string attached to the axel of the large pulley at one end and cylinder B at the other end?

topsquark