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

An object with mass 2.0 kg is dropped from level A in the figure below.

a) In which of the selected levels A - L is its kinetic energy 14 J?

http://img40.imageshack.us/img40/9245/0aup.png [Broken]

**2. Relevant equations**

T = 1/2m*v^2 ?

Or P = m*v ?

**3. The attempt at a solution**

Using the first equation I got: = 0.5 * 2 * (9.81)^2*0.1 = 9.62 J. ( I put the 0.1 at the end to find out the kinetic energy per square(0.1m)

14/9.62 = 1.455 (To find out how many squares it would take to achieve 14J)

Using the second equation: 2.0 * 9.81*0.1 = 1.962 J (Again 0.1 to find out the kinetic energy per square)

14/1.962 = 7,1355 (and how many squares it'd take to achieve 14J)

I got a right answer at this problem but he didn't tell me which one was correct and I have a test tomorrow and really need to understand which one is right. Any help is greatly appreciated.

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

**2. Relevant equations**

**3. The attempt at a solution**

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