Homework Help

Three questions. 1) A skier has just began descending down a 20 degrees slope. Assuming that the coefficient of kinetic friction is 0.10, calculate the acceleration of the skier and the final velocity after 8 sec. We don't have enough information to solve this...or am I missing something? 2) A traffic light with a mass of 30kg is hung in equilibrium by 2 wires, one at an angle of 45 degrees, the other at an angle of 37 degrees. Find the tension in the two wires. 3) One bucket weighing 25N is hanging by a massless cord from another 25N bucket, which in turn is hanging from a third 25N bucket. All three are being lowered with an acceleration of 1.5m/s^2. Cal…

Does anyone know how to determine the hydrated ion that affects the pH of a solution? Ex. NaCl solution, NaCH3CO2 solution, ect. I think it would be the Cl- ion in a solution of NaCl, but not so sure... Merged post follows: Consecutive posts mergedDoes anyone know?.... : -)

Nevermind! All set!

What is the Maximum work done by a nickel-cadmium cell under standard conditions as 1 mol of Cd is used up and if the emf of the cell is 1.4V?

Can someone tell me if I am writing this equation right? I am trying to show the ion that is reacting in the solution. The solution: Al2(SO4)3 Equation: Al^+3 + H2O <----> Al(OH)^+2 + H^+

What is the balanced equation for NaH2PO4 + H2O? Is it NaH2PO4 + H2O ----> PO4^3- + H3O^+ + 2Na^+ ?

Problems resolved.

Hey guys, I'm a new member - In my first year of biomedical science. My Biochemistry module consists of 50% examination (human metabolism) And 50% consists of practical write ups. I'm confused about one graph that is required, the practical in question consists of "estimation of reducing carbohydrates" and "enzymatic and acid hydrolysis of glycogen" Values aside.. I need to plot the following graph on the latest version of excel: Standard curve of concentration and absorbance - done this with no problems. On the SAME graph, I must also plot: Absorbance against time, Glucose equivalents against time, %Hydrolysis against time. Anyone have any id…

Another question i need a bit of help on. The Total length of Calf Thymus DNA is several million base pairs long, how is this reflected in your experimental observations? ok so i have a photograph of the gel i made. and i can see straight long lines of DNA.

Consider the case of a disk of radius a, carrying a surface charge density σ that varies linearly with the distance from the centre of the disk. If the disk rotates about its symmetry axis with an angular velocity of ω, calculate the magnetic field B a distance z above the midpoint of the disk. What is the electric field at the same point? so what I did was I said digma= cr c=constant and v=omega r so surface current I=sigma v = c omega r^2 now using amperian loop we have int (B.dl) = mu I(enc) i used an amparian loop with one vertical side corssing the centre with width of r and height of z above the disk (and below, and we have two vertical parts) so …

Hi, I would really appreciate someone helping me out with this problem or at least showing me how to go about calculating it. Thank you! ---------------------------------------------------------------------------------- Q) Suppose there is a gene with two alleles D and d in Hardy-Weinberg Equilibrium. Further suppose the d allele has a frequency of 0.4 and causes trait Y in a recessive fashion. a) What is the prevalence of individuals without trait Y? b) What is the probability that two individuals with trait Y will mate (given the assumptions of Hardy-Weinberg equilibrium hold)? c) What is the probability that an offspring of the above mating will not h…

Hi everyone, ok this is my first thread on here. I am having problems with one of the questions, if anyone could give me some advice/hint on it. A DNA molecule is 48000 base pairs long. it is cut by a restriction enzyme (Hind III) into 8 basepairs, i m supposed to see 8 bands on the gel photograph but can only see 6. Ok, my teacher said this is because we used ethiduim bromide as a stain, but i dont understand how bromide is related to any of this, i have searched properties of bromide on the net but cant find anything related i would be grateful if anyone could help

Hi, i have another question which i need help with. Bacteriophage DNA is 48000 base pairs long. Hae III cuts it into 206 peices. Hind III cuts it in 7 places, whilst another 6-cutter Pst I cuts it into 28 peices. Why the diffrence? I am thinking is this because they are specific ? as in 6-cutter, 4-cutter etc? or is it something to do with DNA sequences?

What is the magnitude of the acceleration that the force will cause when applied to a car with a mass of 1.1x10³Kg Then calculate the final speed of the car (above) assuming that it was standing still initially and that the force of 5.0 x 10³ N is applied for 6.0s Why would the car take longer to reach the calculated speed if the car's mass was 1.4 x10³Kg. which part of newtons second law would explain this. THANKS. xxx -

The questions asks to use mathematical induction to prove the truth of the follow for [math] n \geq 1 [/math] [math] a^n - b^n [/math] is divisible by [math] a - b [/math] for any integers a,b with [math] a-b \neq 0 [/math] Proof Attempt: [math] n = 1[/math] [math] a^n - b^n = a - b [/math] [math]\frac{a - b}{a - b} = 1 [/math] Now suppose that [math] n = k [/math] and the statement is true for [math] n = k [/math] We must show that the statement is true for [math]n = k + 1[/math] I tried using long division as it was suggested as a hint to consider the remainder: [math] a^{k+1} - b^{k+1}[/math] divided by [math] a - b [/math] …

Having problems with solving a few of these questions and some help which would be much appreciated. 1. A speed skater reduces her velocity from 12m/sec to 6m/sec in 5 seconds. Find: a) acceleration b) velocity at the end of the third second c) average velocity d) distance covered during the 5th second period I found acceleration to be -1.2m/s^2 but I'm having trouble finding the distance traveled to work out velocity and the rest from there... 2. A sprinter covers the first 10 meters of a 100m dash in 2 seconds and the second 10 meters in 1.5 seconds. Find: a) average velocities over the 0-10m and the 10-20m segments of the race. ok so 0-10m…

Why does it take longer to orbit the sun the further a planet is form the sun??? Does pluto travel at a slower pace than Earth, if yes why?? Does the further you are from gravity (the sun) mean the slower you travel? if yes why?? thanks BTW i am in high school so please don't give me an information OVERLOAD!! Although i would like detail!!! HW VERY URGENT!! Thanks!

Hi there, a few weeks ago I did a chemistry experiment on back titration. However, I misplaced the worksheet given to me with questions on the practical work we did, hence left it til the last minute. Now I've found it and I'm having trouble with some of the questions. On top of that my chemistry teacher says he will fail me if I don't hand this by next lesson. Below are the intructions to the experiment that we did and the relevant questions given. I think it's a pretty common experiment so many people here would probably be familiar with it (or have done a similar experiment). If anyone could help me out just this once that would be appreciated. And I'm not asking for s…

I am doing a Mathematical Induction out of the book with solution. I don't see how the LHS is equal to the RHS. [math] 1^2+2^2+3^2+...+(k+1)^2 = (1^2+2^2+3^2+...+k^2)+(k+1)^2 [/math] Expanding [math] (k+1)^2 = k^2 + 2k +1 [/math] What am I missing?

[math]\sqrt{8+2\sqrt{7}}[/math]+[math]\sqrt{8-2\sqrt{7}}[/math]

makes absolutely zero sense to me how a misfolded protein without any instruction from nucleic acid can infect cells. can someone help?

Hi everyone, I need help understanding what this question is asking: How is access to medical care important from an ecological perspective of childhood psychopathology? I could answer "how is access to medical care important" but then I get lost when I see the rest. I have no idea what the ecological perspective of childhood psychopathology even is. I don't know what the ecological perspective is but I'm guessing it has to do with one's environment. I believe that psychopathology has to do with mental and behavioral disorders but when I put it all together, it still confuses me. Can someone please explain it to me? Thanks in advance for any helpful replies.

I am having trouble determining what NaClo + Na2S2O3 create in a balanced equation. What gets canceled out, if anything?

I was recently laid off and can no longer afford the $50 an hour tutor for my Son with ADD in his Science Foundations class, and am now going to be trying to help him myself. I don't have much time to finish this stuff however since I'm now working a lower paying job longer hours, etc. I've attached what I need to help him where here on the Forum, and I will PayPal you $20 if you can finish this by this weekend! I'm sure some of you folks would actually enjoy this!! Just send me a private message and I will respond promptly... Thank you and have a great weekend everyone, Robert Holloway Bakersfield, CA Study Guide 2.doc

Hi Guys! I'm busy compiling a report on the effects of gravity and part of my assignment is to state: how you can use the value of "g" (gravitational force) as a tool to determine where a person is on earth. I have already spoken about central fugal forces etc, I just need to know how you can use "g" to determine your position