(Statics)Hammer and nail force and tension

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The discussion focuses on calculating the forces involved when using a hammer to remove a nail, specifically the tension in the nail, the force exerted by the hammer, and the direction of that force. The user attempts to apply equilibrium equations but struggles with the calculations, particularly in distinguishing between summing forces and moments. They arrive at an estimated tension of 844N but are uncertain about the accuracy of their approach for the other calculations. Clarifications are needed regarding the direction of the force and the proper application of free body diagrams. The conversation emphasizes the importance of correctly summing forces in both x and y directions to achieve accurate results.
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Homework Statement


http://img4.imageshack.us/img4/1116/hammery.jpg
A block is placed under the head of the claw hammer to aid in removing the nail. Assuming that the hammer will not slip at point A...

1) What is the tension in the nail rounded to the nearest Newton
2) The magnitude of the force exerted by the hammer at A rounded to the nearest Newton
3) The direction of the force exterted by the hammer on the block at A rounded to the nearest degree.

Homework Equations



The three equilibrium equations
Sum of x forces = 0
Sum of y forces = 0

The Attempt at a Solution

I'm pretty sure the angle is irrelevant in 1 - It's simply finding the moments around A
ΣMA = -200*0.211 + T*(0.05) = 0
which got me an answer of 844N

for part 2) trying to draw a free body diagram (including the downward force of the nail) but I'm not sure if I'm calculating anything quite correctly

http://img854.imageshack.us/img854/1264/hammer2.jpg

ΣFx= (200*cos 24)*(0.211) + something = 0
ΣFy = -844*0.05 + (200*sin24) ? = 0

maybe? but probably not - I'm stabbing numbers in the dark. I know the answer should be around 44kN
part 3) isn't the angle just the angle of the pull in the negative direction? (so -66 - I could be wrong, getting help in part 2 will help part 3 I'm sure.)

Any help appreciated :shy:
 
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1) is good. For 2), you should be summing forces in both directions, but you seem to be trying to sum moments in some cases.. The x and y components of all forces, including the unknown force components at A, must add to zero. For c)., the angle is correct, but you need to clarify the direction, and explain why.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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