Find the maximum spring compression

[Capncanada]

Homework Statement

A horizontal spring with k = 71 N/m has one end attached to a wall and the other end free. An 95 g wad of putty is thrown horizontally at 3.7 m/s directly toward the free end.

Find the maximum spring compression.

Homework Equations

W=1/2kx^2

The Attempt at a Solution

Tried squaring the 3.7m/s to get 13.69m^2/s^2 and multiplying that by the weight of the putty to obtain 1.3J, the work done.

Plugging that in...

W=1/2kx^2
1.3J=1/2(71)x^2
x=0.19

which is incorrect.

 

[cepheid]

Tried squaring the 3.7m/s to get 13.69m^2/s^2 and multiplying that by the weight of the putty to obtain 1.3J, the work done.

Multiplying it by the mass of the putty, not the weight.

In any case, I suspect you are missing the factor of 1/2 in the expression for the kinetic energy.

 

[Capncanada]

I doubled the KE when I multiplied the 1/2 over in the second step, is that what youre talking about?

 

[cepheid]

I doubled the KE when I multiplied the 1/2 over in the second step, is that what youre talking about?

I'm saying the KE is not 1.3 J, it's half of that. You computed 1.3 J using mv² when you should have used (1/2)mv².

 

[Capncanada]

Got the right answer after rounding it properly haha. Thank you, that's all for tonight. :)

 

[adelinebovi]

Can anyone help me with this issue??

A block of mass m is dropped onto the top of a vertical spring whose force constant is k. If the block is released from a height h above the top of the spring then what is the maximum compression of the spring??

Waiting for your replies.

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