Homework Help

I haven't been lurking for awhile.. but I'm back with a couple of questions. Q1: What is a "control" sample? Q2: Why is it important to have "controls" in your experiment? I do roughly know what a control sample is, but I need the proper definitions. Your help would be greatly appreciated.

Are there any web sites which provide lots of practising questions or problems for the maths, physics, chemistry, biology? I'd like to have far more practise during Christmas holiday.

Hey everyone, Since I am carrying all honors classes, I have more to worry about than science (as hard as that is to believe). Does anyone know of any good homework, in general, forums? things consisting of English, philosophy, History, geology (for some reason we are learning plate tectonics in biology class, and Im so lost), and languages, like lets say german If there isnt any out there with this sort of components, I guess I'll have to make one- I might just need some help with that too Thanks!

can anybody help me with ma physics assignment?? well, we are supposed to research an interesting technology about Physics i can do the job, but i don't know what to base my research on............ can anybody help me please?? i wanna do something about nuclear physics....... so that's quite all i can say today bye

Hi, I have this one question left. This asks bit thinking so anyway, allow me to reveal it. Question: How are respiration and photosynthesis connected? Why are they important to life on earth? What is the "big picture" of energy flow, as it is manifested in respiration and photosynthesis? My answer (which I hope to be accurate): Respiration and photosynthesis are connected that the energy (which is the sunlight) is first transferred by photosynthesis, forming glucose. Then glucose is used on respiration to form ATP. These two process are important because those two processes take energy from the outside, change the form that can be used to run the cell. "B…

Hi all new user bob's the name, if any one could answer it, it would be so helpful Q.What is the principal mechanism for the formation of tarnish on silver?

If a freshwater fish has a short loop of Henle since it can just excrete all its ammonia, doesn't it also excrete all its glucose and other stuff inside its blood since its also not filtered back into the blood?

Here is the question that I need help on. This is quite simple but my solution is, very very long, and I'm not sure whether I'm right or not. You have a winged red-eyed fruit fly. Design a cross to determine whether the fly is heterozygous for either or both traits. Use a Punnett square to show all possible crosses.

Hello, My names Nadine and I have a Protein structure essay to write. I've managed most of it but Im stuck on the question with the most marks!!! Please help me I don't want to fail! Here is the paper as a whole. Desribe how you would analyse the structur of a protein.Include the following in your essay: *A brief outline of protein structure (10 marks) *A description of the methods which can be used to obtain a pure sample(10 marks) *A description of tecniques which can be used to identify the amino acid composition(10 marks) *Details of the tecnique(s) used to work out the sequence of the primary structure (30 marks). Im stuck on the last tw0o bull…

What are the functions of counterweight in a lift system? I could only know of the advantage when the lift is up. In fact, it is supposed to have lots of reasons.

1.Which newton's law describes inertia is proportional to mass? 1st or 2nd? 2.An object is on a slope, the graph of v-t shows that there is negative acceleration, how do you explain it ?

I am trying to calculate whether someone would break their leg when jumping off a 4m wall. Check this out and please comment on if it is correct. Thanks. Will I Break My Leg If I Jump Off This Wall? For the physics presentation I will be including a calculation to show whether someone will break their leg if they jump off a wall. I already know these certain figures: the boy weighs 65 kg and the wall is 4m high. This calculation will only be an estimate but should give a rough idea of how to go about working this out and we will have to go through a few equations to get to the tensile stress. First we should calculate the speed that the person is travelling at…

i was given this hoemwork assignment and i just thought that i would throw it out there to see if anyone could help me out. if someoneis speaking normally, and you were to record it, then the sound would be normal. however, if you were to take a simple portion of that speech and loop it, after a while it would seem as though the person was singing, if you wer eonly listening to the looped secttion. whenever you listen to the entire thing again, everytime you hear that part, it sounds like the person is singing, even though it is just normal spech. any reason why?

Hi all! was wondering if anybody could help me out with the method for this question..... Ive got a physics for chemists test tommorrow in uni since I havn't done A-Level Physics before. Ive been going through a couple of questions as part of my revision which most of them I have been getting the right answers... Ive just recentely come across this question and its really puzzling me how to get to the right answer.... Question The blades of a rotary lawn mower are 0.25 m in radius and have a maximum rotation rate of 3,700 revoultions per minute. Calculate the velocity at the tip of the blade at the maximum rotation rate. [Answer: 97 m/s] All repli…

So, i'm sitting in my Physics class, the bell goes, and everyone packs up, my teacher screams as we're all leaving "HOMEWORK: FIND OUT WHAT GIBB'S FREE ENERGY THEORY IS!", and after a google search, i find nothing. So i thought i'd ask here!

Hi, I got two questions to ask. I have an answer (which I'm going to post) that I think is a hundred percent right but I just want to be sure. I think I have the concept right but only thing that confuses me is whether I had answered the questions ENOUGH. Here goes: 1. What does "carboyhydrate" means? Write the formula for glucose. Does the formula reflects that glucose is carboyhydrate? Answer: "Carboyhydrate" means carbon and water (I didn't put this but more clearly, carbo is carbon and hydrate is water). The chemical formula for glucose is C_6 H_12 O_6 (Wish I can use something like LaTex). The glucose's formula shows that it's carbohydrate because fir…

First, before I proceed on asking for my answer, I want to clarify myself on whether plants do respiration and then the animals or any other heterotroph eat them and the respiration occur AGAIN at them.

Hi. I'm having a lot of problems with a science project. This is what you need to do, blow down 3 pieces of paper one by one from around 10 feet away. Sounds easy huh? Well here's the catch, you can only use cardboard, paper, tape, glue, straws, and trash bags. AND it can't be longer than 29 inches. Some help would be greatly appreciated. Thanks in advance! ~Nap

I am not using this to cheat, I am using this to help me with study for a test. I can find them myslef sue to the fact that I am in an accelerated program and I am at terrible risk of being kicked out if I dont get good marks in Maths, so I am studying my arse off on that. Thank You 1 Write meanings for the words anaerobic and aerobic. 2. What is the difference between respiration and photosynthesis? 3. What factors are needed for photosynthesis to occue? 4. Write both word and symbol equations for both respiration and photosynthesis. 5. What is a stomata and why is it important? 6. How does water andnutrients travel into the leaves of a plan…

First in a series. This is based on nerves and hormones Here are some questions about some sciences. Please make your answers detailed, but please don't crap on. If you do not know the answer, just leave it 1. What is the difference between the central and peripheral nervous system? 2. Write definitions for the following words: neuron, receptors, effectors, stimuli. 3. Explain how a nerve impulse moves from one nerve cell to another 4. What is the difference between the left and right side of the brain? 5. What are the following parts of the brain responsible for: hypothalamus, pituitary gland, cerebrum, pineal gland? 6. Explain how inf…

Hello everyone! What are three statements of the CELL THEORY? Why can we reasonbly sure sure that the cell theory is true? What is the difference between a PROKARYOTE and a EUKARYOTE? What are the similarities between PROKARYOTE and EUKARYOTE cells? What is the function of the CELL WALL? Why is cell wall found mostly in plants? What is the job of the nucleus? Thanks!

Wow, I know this is incredibly off the subject of science, but I really dont know who to ask. What are several theories as to Homer was (This is the ancient greek Homer, not the drunken cartoon)? What was his view on heroism (Altruism/Egotism)? How was Homer interested in human phychology- why? Thanks for any help possible

Im doing a project on thomas edison and i was wondering excatly how many inventions did he invent.

These are two questions from an assignment which I just don't get. I'm in grade 12. I just want to be pointed in the direction, not given the answer. I wanna make sure I know this for the test, my teachers hard 1) A 1.00kg mass and a 2.00kg mass are set gently on a platform mounted on an ideal spring of force constant 40.0N/m. The 2.00kg mass is suddenly removed. How high above this starting position does the 1.00kg reach? I was thinking of determining the energy at equilibrium, because Ee = 0 and Ek = max at that point...but it would become zero, would it not? or, could i equal Ek1 + Ee1 = Ee2 + Ek2? I dunno... 2) A ball of mass 0.25kg is thrown vertically u…

I have looked all over the internet and i can not find anything on the experiment that let to the discovery of the Electron cloud atom model, could somone help me.