Primarygun

Thank you very much.

How does a nucleus control a cell membrane?

According to Newton's third law, v t p u o u o It is a rope with a wheel,v. If 50N is applied from u pulling towards the ground, what's the reaction force? From o to p ?

Normally, my base with two lights on, one green light and one red light. In the case, it only shows one red light, and the CD Rom Driver was continuously with a light but it didn't open its rom when I press it.

Recently, I found that my computer was very noisy and it makes many noises. Perhaps, it emits some waves together with some harmful radiation. I don't know but I dislike them very much. I switched off the power button on the plug. Later, when I switched it and the power button of my computer on again, my computer just had one light abnormally. Normally, it has two light on when it is operating properly. Of course, it couldn't be used at the moment. Nothing is on my screen. The connection of my monitor to my machine seemed to be out of order but I didn;t think so. I waited several minutes and it ran again. It needed to be "warm up". What's the matter with it ?

Higher the temperature is, lower the gas solubility and higher pressure .

The product you get depends on the electrochemical series, the concentration, the nature of the electrode.

By the way, I think using domestic electricity from power station is too dangerous. Better use cells. They are enough and safer.

All in all, acid will decompose in water to give mobile ions, Such as H3O+ , SO4 2-, SO3 2-, NO3-............... In brief, acids are electrolytes. They conduct electricity well due to the presence of moblie ions. It conducts due to the movement of mobile ions. Pure water merely has mobile ions. Since it is a molecule, the electronegativity of oxygen and hydrogen is not differ to much, the probability of water molecules pull off an ion out from an other water molecule is low. Hence, water is not a electrolyte. Adding small amount of dangerous sulphuric acid make it perfect. By the way, YT, how to extract potassium from its own ore?

I don't think so. The water temperature is very low. Also, the oceans are very large and they need to spend a lot of energy swimming and keeping their body warm. Big waves, sharks, rains, factors which may make the situation worse.

I downloaded a MS file about maths. I don't know why the symbols and numbers cannot be shown clearly and correctly. Anyone help me>?

Either sulphuric acid (dangerous) OR sodium sulphate(harmless),right?

What's the relationship between the organisms in contact in the trophic level? Flea is one level above a dirty monkey.

Consumer should be replaced by predator. Oh sorry:P

Thank you. When does a green plant act as consumer?

Flower--->Cow---->Human Is cow act as producer when it is eaten by a human? Finally, human died and their bodies are decomposed by bacteria. Then plants absorb the mineral salts provided. Are the salts carry energy to the next trophic level? Dead bodies--->bacteria--->Plant ( Is this a energy flow?)

Thank you

Thanks. It is very useful .

Never mind, I got the answer. It is b2.

Imagine there is an object on the surface. The surface is uniform smooth(with same friction over the all surface and friction is greater than 0). Let's define the friction be f. Act a f force to horizontally to the object continuously, it is continuous added. It is obviously stationary. I'm quite confused of here then. If there is 1N force pushed to it in the same direction to the f force added by hand. What will be observed? a.Move with acceleration first, then remains the velocity later on. b.1.If f>kinetic friction, then the object accelerates first then decelerates to stop. b.2. If f> kinetic friction, then the object will accelerates continuously forward. Which one is correct?

It is very difficult to understand all tricky things from a thin physics or chemistry books. Anyone has good web sites related to science notes?

Solve in terms of h, G, k and M?

Yes. Using a calculator can find the value of sin (180-a)=sin A But this definition is proved inside the geometry circle first. Do you know the proof?

Yes. Using a calculator can find the value of sin (180-a)=sin A But this definition is proved inside the geometry circle first. Do you know the proof?

Actually, the 2nd question is very silly asked by me. LOL. Inertia always accompany 1 st in textbooks. However,I think it is the 2nd law.