Science & Mathematics - 11 October 2006

So why can a pin go through a balloon without popping in a certain way? in my class my teacher demonstrated this and I don't understand how it does that . We are learning about semi-permeable membranes and what not. How does it work???

2006-10-11 17:51:30 · 5 answers · asked by Jenna J 2 in Biology

Please help with this physics problem.

A 4.00 kg block is placed on top of a 12.0 kg block that rests on a frictionless table. The coefficient of static friction between the two blocks is 0.700. What is the maximum horizontal force that can be applied before the 4.00 kg block begins to slip relative to the 12.0 kg block, if the force is applied to each of the following?

(a) the more massive block

= 109 (.7 * 16*9.8)

(b) the less massive block

How do I do part b?

The answer for part b is not, 53.85, 82.32, 27.44, or 109.

2006-10-11 17:50:45 · 4 answers · asked by Confused 1 in Physics

what is a qualitative predictions???
i need to know for a chem lab.

2006-10-11 17:48:26 · 2 answers · asked by dsds 1 in Chemistry

2006-10-11 17:47:15 · 7 answers · asked by ourdoorsangler 1 in Mathematics

2006-10-11 17:46:23 · 10 answers · asked by SWEETOO J 2 in Physics

My sister asked this same quesation under the social science section, she doesn't know the diff between social science and science (biology, chemistry, physics, and meteorology) sorry..............

2006-10-11 17:45:26 · 6 answers · asked by shadowpal2 2 in Earth Sciences & Geology

What 2 ways do cancer cells differ in their mitotic processes compared to normal cells that result in the growth of tumors?

2006-10-11 17:44:45 · 6 answers · asked by nekomimi 1 in Biology

2006-10-11 17:40:52 · 9 answers · asked by indian g 1 in Weather

since like charges repel each other...

2006-10-11 17:36:09 · 8 answers · asked by Tim 2 in Chemistry

Sixty percent of those present at the performance were neophytes. If 200 present were not neophytes, how many people attended the performance?

2006-10-11 17:33:18 · 8 answers · asked by Anonymous in Mathematics

-18-6k=6(1=3k)
-18-6k=6+18k
+18 +18
-6k=24+18k
+6k +6k
24=24k divide by 24
n k = 1

2006-10-11 17:29:29 · 6 answers · asked by Shawanda M 1 in Mathematics

At some point in the chain no matter how small you go something had to get the ball rolling. I've never seen an object move or be created without outside force.

2006-10-11 17:27:29 · 30 answers · asked by joshjones007 1 in Astronomy & Space

how do I solve
Logbase5(x+1) - Logbase5(x-1) = 2

2006-10-11 17:21:35 · 6 answers · asked by ctjarig 1 in Mathematics

Find the point between Earth and the Sun at which an object can be placed so that the net gravitational force exerted by the Earth and the Sun on that object is zero.

Me=5.98x10^24
Ms=1.991x10^30
G=(6.673x10^-11)

F=(GM1M2)/r^2

2006-10-11 17:20:39 · 5 answers · asked by Anonymous in Physics

Let me clarify my question, if two conductors of different materials placed in contact with each other and one material is heated, the heat energy is transferred to the other material by conduction, as a result the temperature of sceond material rises.
.
Now let us take our query, as heater coil gets heated the contact wires must also get heated due to the heat conduction from the heater coil. But this is not happening in the real case. (In essence the temperature of the contact wire almost remains unchanged) What is the reason?
Please consider this question in a very fundamental manner. For example if we connect a small piece of nicrome coil to a lead acid battery via a copper wire without any insulation the same thing is happening.
re Review

2006-10-11 17:19:25 · 5 answers · asked by Anonymous in Physics

Well theres a problem i need help with. It says some one throws the object up in the air and they give you an initial speed im pretty sure. They want to find out what the maximum distance it will reach before the object falls. I was obviously paying attention about dropping objects, but how do you do this one?

2006-10-11 17:18:59 · 5 answers · asked by playaxn1 2 in Physics

How big is the population now?

How far has their territory expanded?

2006-10-11 17:17:39 · 2 answers · asked by Anonymous in Zoology

Let me clarify my question, if two conductors of different materials placed in contact with each other and one material is heated, the heat energy is transferred to the other material by conduction, as a result the temperature of sceond material rises.
.
Now let us take our query, as heater coil gets heated the contact wires must also get heated due to the heat conduction from the heater coil. But this is not happening in the real case. (In essence the temperature of the contact wire almost remains unchanged) What is the reason?
Please consider this question in a very fundamental manner. For example if we connect a small piece of nicrome coil to a lead acid battery via a copper wire without any insulation the same thing is happening.
re Review

2006-10-11 17:17:28 · 2 answers · asked by Anonymous in Physics

if n is an even number, then n is exactly divisible by 2. n is an even number.... wat do i do?

2006-10-11 17:17:18 · 3 answers · asked by georgia a 1 in Mathematics

-(7-4x)=9
-7+4x=9
+7 +7
4x=16 divided by 4=
x =4

2006-10-11 17:16:21 · 10 answers · asked by Shawanda M 1 in Mathematics

Refer to this:
Fe2O3(s) + 2Al(s) 2Fe(l) + Al2O3(s)

2006-10-11 17:15:30 · 3 answers · asked by phys 1 in Chemistry

During nucleophilic substitution reactions, what happens if you take too long and leave the products open (uncapped)?
Why do you have to cap the products for the most of the time?

2006-10-11 17:15:14 · 4 answers · asked by organicchemilove 2 in Chemistry

As shown in the figure below, a uniform electric field has magnitude E = 290 N/C and is directed to the right. A particle with charge +3.6 nC moves along the straight line from a to b.

(a) What is the electric force that acts on the particle?

b) What is the work done on the particle by the electric field?

(c) What is the potential difference Va - Vb between points a and b?

2006-10-11 17:14:14 · 2 answers · asked by p_rob22 1 in Physics

i am currently a freshman at UCSD with an interest to pursue a career in medical forensics. i do not wish to be a crime scene investigator, instead i wish to be the medical examiner herself, the person who does the autopsy and determines the cause of death.

2006-10-11 17:13:39 · 7 answers · asked by Anonymous in Medicine

2006-10-11 17:13:38 · 4 answers · asked by chinjewel 2 in Chemistry

2006-10-11 17:13:15 · 2 answers · asked by phys 1 in Chemistry

Describe the distribution of a sample means(shape, expected value, and standard error) for samples of size n = 36, selected from a population with µ = 65 and σ = 12.

2006-10-11 17:11:35 · 2 answers · asked by .......... 4 in Mathematics

2006-10-11 17:04:52 · 7 answers · asked by Shawanda M 1 in Mathematics

2006-10-11 17:04:00 · 11 answers · asked by Anonymous in Zoology

2006-10-11 17:02:11 · 12 answers · asked by nativecherokeeindngrl 1 in Other - Science