Recent content by rowkem

Homework Statement A 10kg box at rest is being pushed on a frictionless surface by a force of 10N. The force is in the same direction as the motion of the box. 10 seconds later, how much kinetic energy will this box have? Homework Equations 1. F=ma 2. Vf=Vi+at 3. Ek=0.5mv2 The Attempt at a...

I've changed the numbers a bit so things work out a little easier Homework Statement The combustion of propane in a BBQ follows the balanced chemical reaction: C3H8 + 5 O2 ---> 3 CO2 + 4 H2O As this reaction occurs, approximatley 3000J of heat is released. If a roast takes approx...

So: we did an experiment to see if sow bugs liked a dry or a moist environment. We put them in a choice chamber and let them choose between a dry environment and a humid environment. We also did a separate control where we gave them the choice between two identical dry environments. My...

Homework Statement How much energy must a 12V battery expend to fully charge a 0.15 uF and a 0.20 uF capacitor when they are (a) in parallel and (b) in series? How much charge flowed through the battery in each case? Homework Equations i: C(eq)=((1/C1)+(1/C2)+...+(1/Cn))^-1 and...

OK - that has help immensely. I realize now that sodium channels are highly selective and I did a quick read up on the topic. Thanks. So - last question. Have plants evolved to have more potassium ion channels than sodium channels? If this is the case, then we can make some conclusions.

Yes, I realize there is much literature on what potassium does, seeing as how that's what typically moves through the transport protein. There isn't lit though, on why sodium is less effective is opening stomata. Could it be that plants have simply evolved to use potassium, and therefore...

Homework Statement So we did an experiment where we put a leaf section in KCl and another leaf section in NaCl. There was a marked difference in the percent of stomata that opening between the two. We let the two sections sit in solution for 60 mins each. The leaves in KCl had almost...

Took a stab at it. Was correct. Thanks everyone.

That would do it. I end up getting 7.53x10^6 m/s. Seems high - thoughts before I submit?

Homework Statement Two stationary positive point charges, charge 1 of magnitude 3.45 nC and charge 2 of magnitude 1.85 nC, are separated by a distance of 50.0 cm. An electron is released from rest at the point midway between the two charges, and it moves along the line connecting the two...

So.. F=Eq E=F/q - we know q but we need F. For it to hang suspended, there needs to be no net force acting on the bead. The electrostatic force is one of two forces acting on the bead; as well as being the F in our equation. So...this "other force" needs to be equal to the...

Homework Statement Two stationary positive point charges, charge 1 of magnitude 3.45 nC and charge 2 of magnitude 1.85 nC, are separated by a distance of 50.0 cm. An electron is released from rest at the point midway between the two charges, and it moves along the line connecting the two...

I know this is probably useless but, I thought I would give it some closure since some replies were filled with snide remarks and little was done to resolve the question at hand. First, I see nothing wrong with the equation, as far as I know, that's the combustion of sucrose and it's balanced...

As Borek said - water has to gain or lose energy to heat and cool, respectively. The enthalpy change is always in relation to the system. Heating: system gains energy: enthalpy change is positive Cooling: system loses energy: enthalpy change is negative Yes, that is correct. Cooling an...

Heh. Your thinking makes more sense...much more. I based that on a limited understanding of natural selection, it would seem.