# Search results

1. ### Finding Ek with force, mass, and time.

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...
2. ### Figuring out the amount of CO2 that goes into the atmosphere when cooking a roast

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...
3. ### Faradays Law - Induced Current

Homework Statement A loop of wire is situation between a wire (Wire 1) that is perpendicular to the loop and another wire (Wire 2) that is parallel to the loop (the diagram has the loop and Wire 2 in the plane of the page, Wire 1 is running "through" the page). Is a current induced, and in...

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 seperate control where we gave them the choice between two identical dry environments. My...
5. ### Archived Charge and Energy for Capacitors in Different Configurations

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...
6. ### Why would leaves in a K+ solution have more open stoma than leaves in a Na+ solution?

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...
7. ### Speed of an electron in an electric field - want to check answer before submitting.

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...
8. ### Speed of an electron in an electric field - trying to find my error.

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...
9. ### Do plants destory auxin intentionally?

So - plants bending towards light. Light kills auxin. Shaded side grows faster so plant bends toward light. Was this an evolutionary mechanism developed by plants? Thinking of natural selection - were plants with auxin more successful since they could p/s more which meant higher rates of...
10. ### Within ourselves, does blood have an expiry date?

I would assume that blood, within us, is only good for so long but, I could be wrong. Also, if it does become "bad", where does it go? How do we get rid of "garbage blood"?
11. ### Electric field from two point charges and then some

Homework Statement A point charge, q1, has a charge of 3.4x10^-9 C. A second point charge, q2, is place 2.1x10^-6 m to the right of q1; it has a charge of -10.2x10^-9C. A) What is the magnitude of the field 8 mm to the left of the centre of the two charges? B) You could also treat...
12. ### Electric field produced by 2 point charges

Homework Statement A small object A, with a charge of -2.78x10^-10 C, creates an electric field. At a point P located 0.250 m directly north of A, the field has a value of 40.0 N/C directed to the south. If a second object B with the same charge as A is placed at 0.250 m south of A (so that...
13. ### Are larger seeds more sensitive to NaCl than relatively smaller seeds?

So, we grew "large seeds" and "small seeds" in a certain concentration of NaCl. We also grew the same kinds of seeds in regular water. The control group data showed that the larger seeds had a longer radicle than than the smaller seeds. The NaCl group showed the same; larger seeds=relatively...
14. ### Do larger seeds need less water to germinate?

Or, put another way, will larger seeds generally germinate more oftern than relatively smaller seeds, in drier conditions?
15. ### Why would smaller seeds be more sensitive to saline water than larger seeds?

So, we did an experiment where we exposed two different sizes of seeds to varying concentrations of salt water. The "small" seeds had, on average, shorter radicles than the larger seeds. So, it seems that smaller seeds are more sensitive to the saline solution. I'm just a little confused as...
16. ### Several questions regarding an ideal gas.

Homework Statement Making jam and then putting it into jars is called canning. The process involves putting the jam into the jars while it’s still quite hot; hot enough to kill germs. While canning some strawberry jam you notice that the lid pops in towards the jam when the temperature drops...
17. ### Using the Fundamental Theorm of Calculus II to evaluate indefinite integrals

Homework Statement Evaluate the following definite integrals using the Fundamental Theorem of Calculus: 1. 1 \int 4 ( (5x2+7x+5)dx ) 2. -5pi/6 \int 4pi/6 (−6sinx+7cosx) dx ) 3. 2 \int 4 ( (e^-4x)/((e^(-4x))+7) dx ) If it's unclear, the number on the...
18. ### How do I determine where a function has a removable and a jump discontinuity?

Homework Statement I am given the following function, piecewise: f(x) = (-x+b) (x<1) 3 if x=1 (-12/(x-b))-1 (x>1, x=/b) I am asked: 1) For what value(s) of 'b' does 'f' have a removable discontinuity at 1? 2) For what...
19. ### Chemistry Help finding moles of pain killer/moles of hydrogen ion in a pain killer w/ titration

Homework Statement Assuming the acid (pain killer) is monoprotic, calculate the moles of pain killer/hydrogen ion in a sample of an unknown pain killer using a titration: NaOH was added to a pain killer solution m[pain killer]=0.40g dissolved in 50 mL of distilled water [NaOH]= 0.15...
20. ### Theory behind electrostatics?

So, I believe I've got the math part down but, I'm having trouble understanding the theory. Can someone briefly explain how conductors work? Grounding? Insulators? Direction of electron flow. Induction? Conduction? Anything else would be great, thanks.
21. ### Medical What are some health/medical discoveries that have lead to even greater discoveries?

Basically, I'm wondering what some of the medical and health related advances that have lead to even great discoveries? This is happening all the time but, I'm looking for some specific examples. Thanks,
22. ### Medical Be honest; isnt ADHD and all these attention/behavioural disorders a bunch of bull?

Be honest; isnt ADHD and all these "attention/behavioural disorders" a bunch of bull? Needless to say, I'm not saying it doesn't exist. I'm sure years and years ago, people thought that schizophrenia and bipolar disorder was just an excuse but, isn't this a little to easily diagnosed? How much...
23. ### Medical What is an area of health research that you think should no longer be pursued?

Hey all, I'm in the process of applying to Uni. and the program I've chosen requires an additional application. That said, the one question on it is: What is an area of health research that you think should no longer be pursued? Why? I've been thinking about it and I could take the...
24. ### Which ∆H should I be using in my chemical equation? In my potential energy diagram?

So, I did 5 labs where I burned certain things and found the temp. diff. in the calorimeter. That said, I calculated the ∆H for the entire system, the ∆H per gram of system substance, and the ∆H per mol of system substance. Im wondering which ∆H I should be putting into my chemical...