Here is the problem I am given,(adsbygoogle = window.adsbygoogle || []).push({});

Two blocks are connected by a string that passes over a massless, frictionless pulley. Block A, with a mass of 2.0 kg, rests on a ramp measuring 3.0m vertically and 4.0m horizontally. Block B hangs vertically below the pulley. Use g = 10 m/s^2 for simplicity.

When the system is released from rest, block A accelerates up the slove and block B accelerates straight down. When block B has fallen through a height h=2.0m, its speed is v=6.0m/s

Using Wnc = (KE + PE) - (KEo + PEo)

I am asked first to identify which term is equal to zero.

Since there is a non conservative force (tension), Wnc does not equal 0

However, the system begins from rest, so KEo = 0

I am then asked to solve for the mass of Block B using the equation above.

with KEo = 0, I know that,

Wnc = KE + PE - PEo, However, I am unsure of how to solve for m since it appears in

all the terms. How can I isolate it?

Am I simply overthinking the problem?

Thanks!!!

-density

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# Homework Help: Using the conservation of energy equation

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