(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Determine the velocity of the 60- block A if the two blocks are released from rest and the 40- block B moves 0.6 up the in cline. The coefficient of kinetic friction between both blocks and the inclined planes is = 0.05.

Here is the given diagram:

3. The attempt at a solution

Since there is a pulley system, I began with the length equation so that i can determine the displacement of A with respect to B.

Δs_{A}= -0.5Δs_{B}

Once everything is plugged in, Δs_{A}= -0.3 (or just 0.3m down along its plane).

Using this, i calculated the change in height as it falls from the top to the next position. Δh = 0.2598076211 m. Then i calculated the normal force exerted by the plane and the force of friction acting on the block A (F_{f}= 14.715 N (directed towards the pulley system). So here's the part that i dont get. Im not sure how to tie everything together. I know that:

Kinetic Energy (T), Work and potential Energy (U)

T_{1}+ U_{1 -> 2}= T_{2}

0.5m_{A}v_{1}^{2}+ U_{1 -> 2}= 0.5m_{A}v_{2}^{2}

From the free body diagram of the isolated mass A, i know that there is a normal force, the weight of the block, and a friction force acting on it. So from this information, I believe that there should be gravitation potential energy (V_{G}= mgΔh), and i feel like the friction force needs to be included as well. So i would integrate the force i calculated, with respect to s (∫F_{f}ds). Then i feel like it should be integrated from 0 -> 0.3. Is this correct so far?

Thanks in advance for any help.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Principle of Work and Energy

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