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verd
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Alright-- Sorry, I have a couple I'm stuck on...
...I'm still a little slow with this, so I make a lot of stupid mistakes-- If you see one, by all means, please let me know.
(Also, pardon the incredibly stupid nature of some of the problems... They're ridiculous)
1.) Your cat "Ms." (mass 7.00 kg) is trying to make it to the top of a frictionless ramp 2.00 m long and inclined upward at 30.0 degrees above the horizontal. Since the poor cat can't get any traction on the ramp, you push her up the entire length of the ramp by exerting a constant 100-N force parallel to the ramp.
If Ms. takes a running start so that she is moving at 2.40 m/s at the bottom of the ramp, what is her speed when she reaches the top of the incline? Use the work-energy theorem.
Okay-- So, moving down inclines I seem to have no problem with, but moving up inclines... eh... I seem to be having difficulty with. I've read somewhere that when you have a constant force, and you're moving up an incline, you just use the same old, W=Fs formula-- which makes sense. But this cat doesn't have a constant force-- Initially the cat does, when it gets a push, but I'm not quite understanding how I compare a constant force with one that isn't constant. (I do know and undersatnd the work-energy theorem.)
Needless to say, I've gotten tons of different answers on this one-- all of which are incorrect. Could anyone point me in the right direction on this one? Work and energy with varying forces?
2.) A balky cow is leaving the barn as you try harder and harder to push her back in. In coordinates with the origin at the barn door, the cow walks from x = 0 to x = 6.9 m as you apply a force with x-component [tex]F_x = -[20.0\;{\rm N} + (3.0\; {\rm N})x][/tex].
How much work does the force you apply do on the cow during this displacement?
This one-- Work and energy with varying forces. I'm having a little difficulty with these, as I'm in Calculus right now... Eh, but I'm not here asknig for a tutorial on integrals, no worries. This:
[tex]W = \int F_xdx[/tex] will be equivalent to [tex]F_x(x_2-x_1)[/tex]?
Is this the correct formula? ...How should I solve Fx?
3.)A block of ice of mass 4.50 kg is placed against a horizontal spring that has force constant k = 150 N/m and is compressed a distance 2.30×10−2 m. The spring is released and accelerates the block along a horizontal surface. You can ignore friction and the mass of the spring.
Calculate the work done on the block by the spring during the motion of the block from its initial position to where the spring has returned to its uncompressed length.
What is the speed of the block after it leaves the spring?
This, too seems to be another of the same problem.
[tex]W = \int kxdx = 1/2kx_2^2 - 1/2kx_1^2[/tex]?
...I initially tried solving this thinking that k2 was not = to 0 -- but apparently that's not correct. Any advice on how to go about this one?
Thank you ten times
...I'm still a little slow with this, so I make a lot of stupid mistakes-- If you see one, by all means, please let me know.
(Also, pardon the incredibly stupid nature of some of the problems... They're ridiculous)
1.) Your cat "Ms." (mass 7.00 kg) is trying to make it to the top of a frictionless ramp 2.00 m long and inclined upward at 30.0 degrees above the horizontal. Since the poor cat can't get any traction on the ramp, you push her up the entire length of the ramp by exerting a constant 100-N force parallel to the ramp.
If Ms. takes a running start so that she is moving at 2.40 m/s at the bottom of the ramp, what is her speed when she reaches the top of the incline? Use the work-energy theorem.
Okay-- So, moving down inclines I seem to have no problem with, but moving up inclines... eh... I seem to be having difficulty with. I've read somewhere that when you have a constant force, and you're moving up an incline, you just use the same old, W=Fs formula-- which makes sense. But this cat doesn't have a constant force-- Initially the cat does, when it gets a push, but I'm not quite understanding how I compare a constant force with one that isn't constant. (I do know and undersatnd the work-energy theorem.)
Needless to say, I've gotten tons of different answers on this one-- all of which are incorrect. Could anyone point me in the right direction on this one? Work and energy with varying forces?
2.) A balky cow is leaving the barn as you try harder and harder to push her back in. In coordinates with the origin at the barn door, the cow walks from x = 0 to x = 6.9 m as you apply a force with x-component [tex]F_x = -[20.0\;{\rm N} + (3.0\; {\rm N})x][/tex].
How much work does the force you apply do on the cow during this displacement?
This one-- Work and energy with varying forces. I'm having a little difficulty with these, as I'm in Calculus right now... Eh, but I'm not here asknig for a tutorial on integrals, no worries. This:
[tex]W = \int F_xdx[/tex] will be equivalent to [tex]F_x(x_2-x_1)[/tex]?
Is this the correct formula? ...How should I solve Fx?
3.)A block of ice of mass 4.50 kg is placed against a horizontal spring that has force constant k = 150 N/m and is compressed a distance 2.30×10−2 m. The spring is released and accelerates the block along a horizontal surface. You can ignore friction and the mass of the spring.
Calculate the work done on the block by the spring during the motion of the block from its initial position to where the spring has returned to its uncompressed length.
What is the speed of the block after it leaves the spring?
This, too seems to be another of the same problem.
[tex]W = \int kxdx = 1/2kx_2^2 - 1/2kx_1^2[/tex]?
...I initially tried solving this thinking that k2 was not = to 0 -- but apparently that's not correct. Any advice on how to go about this one?
Thank you ten times