Relationship between applied force and frictional force Could anyone explain to me why the applied force is equal to the (kinetic) frictional force when an object moves across a surface perpendicular to the ground at a constant speed? My class just started the Dynamics unit and I am confused about this..
help on biology homework here's my statement- When fresh water was added, the cell turned hypotonic, thus making the cell appear swollen. When salt water was added, the cell turned hypertonic, therefore making the cell (cytoplasm) to shrink. does this statement sound right? if wrong, what do i have to fix? edit: sorry, this is a plant cell (red onion to be specific :D) edit2: alrighty guys, thanks for the help! btw this is for grade 11 adv bio class just in case if you were wondering!
Difference between diffusion and concentration gradient? What's the difference between diffusion and concentration gradient? My teacher gave us definitions for both, but I don't really understand where's the difference... diffusion: process by which molecules of a substance move from areas of higher concentration to areas of lower concentration. concentration gradient: a gradual change in the concentration of solutes in a solution as a function of distance through a solution. To me it seems like concentration gradient is just worded differently but means the exact same thing as diffusion... can anybody clear this up for me? btw, English isn't my first language, so I might not be understanding something >_>
first day of university? how is it like? what should i be prepared for? looking for advices!
Help with Physics sound waves please So... the question is this: The sound wave from a person's voice has a distance from compression to rarefaction of 9.0 cm. If the frequency of the sound is 2000.0 Hz, what is the temperature of the air on this day in the tropics? I'm guessing that the temperature is going to be high since the question stated that this is in tropics... but I got something like -256'C x_x can somebody explain to me how I'm supposed to solve this?
LHopitals Rule what do i do if i were to follow the rule given by my teacher (if degree of numerator>degree of denominator, then Horizontal Asymptote does not exist), the answer should be "does not exist/no solution". however- the answersheet and wolframalpha are telling me that the answer is Infinity... someone please enlighten me
urgent help needed on basic trig oh my god, so ive been on this question for +30 mins now. so here's my problem... please please [b]please[/b] explain to me what im doing wrong o.o once you guys tell me what the problem is im so gonna freak out because of my dumb-ness... anyways <A = 31 degrees, side b = 76 units and side c = 183 units. I need to determine the measure of the obtuse angle "x". sorry for not being able to provide a diagram :~( since i cant use the sine law, i decided to use the cosine law to first get "a". a^2 = b^2 + c^2 - 2bcCosA 76^2 + 183^2 - 2(76)(183)Cos31 39265 - 23842.96564 a = 124.1854837 now, I have "a", so I could use the sine law to determine "x". c/SinC = a/SinA 183/SinC
physics gr.11 question about tensions Hi, so I designed a problem for myself to solve, and i solved it, but I don't know if its right. can you guys confirm if i got this question right? I got the answer of....the tension of rope A is 71.96N and the tension of rope B is 32.13N. g = 9.81m/s^2 edit: i didn't carry all the numbers from the calculator so there could be a little error with my solution, like ~0.5
I found out im into older men im 18 i found out im into guys 30+ what do
Psychology sleep survey Hello, I'm doing a survey for my psychology class, which is on sleep deprivation. This survey mainly targets teenagers from age of 14 to 18 specifically, but doesn't mean you can't participate. Thanks in advance for participating :D [url=http://www.surveymonkey.com/s/J22VDML]Part 1[/url] [url=http://www.surveymonkey.com/s/J2NNQNK]Part 2[/url]
Help understanding inclined planes for physics So, here is the question - A cyclist coasts down a ramp that is 1.5m high and 12.0m long. I need to find the acceleration if friction is ignored - and I think I need to do: ma = mg*Sin7.18, because this gives the right answer of 1.23m/s^2. However, I need help understanding why I need to substitute these formulas to get the correct answer. Could anyone explain this to me? If this method is incorrect, can anyone tell me the correct way to solve this problem? EDIT: by 12.0m long, I mean the hypotenuse is 12.0m long! I was taught to assume that the given length was always the hypotenuse.
difficult physics questions for gr11 hello, i'm taking a kinematics test tomorrow, and i need some slightly difficult questions to solve to get prepared. if you have any difficult questions [i]for my grade level[/i] , please leave some! i consider questions like these slightly difficult: Two students working on a physics assignment to find out how far a window is from the roof of a building drop a ball over the edge of the roof. The ball takes 0.1000s to travel from the top of the window to its bottom, a distance of 1.00 meter. Assume the acceleration of gravity is 10.0m/s^2 (yes i know its 9.81) in this problem and calculate the distance from the edge of the roof to the top of the window. edit: the only equations i have are d=Vit+1/2at^2,
Help needed on laptop choosing Hello, so I'm trying to get a new laptop for myself, most likely for better game play for maple :3. Anyways, since I know nothing about computers and their processors, ram, and stuff like that, I need your help if this fits the recommended setting for maple. (what I'm getting) Asus - 11.6" Touch-Screen Laptop - 4GB Memory - 500GB Hard Drive - Steel Gray Hairline ENERGY STAR Certified Windows 8 64-bit Technical details: 3rd Gen Intel® Core™ i3 processor; 11.6" display; 4GB memory; 500GB hard drive, UMA graphics (maple requirement) Windows XP or later Processor Pentium Dual Core or equivalent Memory 1GB RAM Hard Drive At least 4GB of free space Graphics GeForce FX5000 / ATI Radeon 9600 or high