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Layan

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Questions221
  • Is this sentence correct grammatically ? ?

    “I am recruiting you to help me improve my English.”

    I don’t know if what I care about is the grammar, I just wanna know if that sentence is correct. 

    It will be followed by:

     “ From now on, I’ll text you only in English, and you can ( and should ) correct me whenever I make a mistake or you think my statement could be phrased better.” 

    Does the follow up have mistakes ? 

    1 AnswerWords & Wordplay6 months ago
  • The more negative the RMP the more excitable the nerve cell ? Help please ?

    "a more negative membrane potential indicates higher excitability because the more negative the potential, the more sodium channels are in the state of closed and capable of opening, while at a less negative membrane potential a higher percentage of channels are in the state of closed and incapable of opening than in a more negative membrane potential." 

    This was written by one of the foreign high achievers in my class and I'm confused by how its true. 

    If the RMP is more negative, wouldn't the neuron need a stronger stimulus for the threshold to be reached ? Wouldn't that make it less excitable than other neurons who are in an env with a less negative RMP ? 

    Biology6 months ago
  • Confused about Nernst equation -Intro to Physiology Help please  ?

    Solutions A and B are separated by a membrane that is permeable to Ca2+ and impermeable to Cl−. Solution A contains 10 mM CaCl , and solution B

    contains 1 mM CaCl2. 

    Assuming that 2.3 RT/F = 60 mV, Ca2+ will be at electrochemical equilibrium when

    (A) solution A is +60 mV

    (B) solution A is +30 mV

    (C) solution A is −60 mV

    (D) solution A is −30 mV

    (E) solution A is +120 mV

    (F) solution A is −120 mV

    (G) the Ca2+ concentrations of the two solutions are equal 

    (H) the concentrations of the two solutions are equal

    Now I know that solution A will have a negative potential difference and I would've assumed the answer was D but I'm confused about the 60mV they provided in the question. 

    The equilibrium potential is the membrane potential at a specific concentration gradient when a specific ion is at equilibrium, correct ? An ion being at equilibrium just means that there is no net diffusion of the ion. 

    If I use 60log(10/1) I'll get 60 mV 

    What is this 60mV ? Is it the equilibrium potential of Ca2+ ions ? If yes why isn't the answer C ?

    Biology6 months ago
  • Should I use the word 'and' before the word 'hence' ?

    Is it okay to say 'and hence' ?

    6 AnswersWords & Wordplay6 months ago
  • Introduction to physiology; will you help explain this simple paragraph on homeostasis to me ?

    Disease is often considered to be a state of disrupted homeostasis. However, even in the presence of disease, homeostatic mechanisms continue to operate and main- tain vital functions through multiple compensations. In some cases, these compensations may themselves lead to major deviations of the body’s functions from the normal range, making it difficult to distinguish the primary cause

    4

    of the disease from the compensatory responses.

    What does this mean ?

    2 AnswersBiology6 months ago
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    Cis trans isomerism?

    I’m slightly confused about the rules

    Should there be at least 1 identical group on both carbons and are these the ones I’m comparing ? 

    For example the picture below 

    Is this molecule cis or trans ? and why ? 

    P.s, I don’t wanna know if it’s E or Z, just cis or trans and why please

    2 AnswersChemistry7 months ago
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    Naming Alkanes With Branched Substituents help please please ?

    What is the common and IUPAC name of the compound In the photo

     and 

    q2. if 2 subtituent groups fall on 2 different carbons the later one in alphabetical order on an earlier C number, do I prioritize the numbering or the alphabetical order ?

    Chemistry7 months ago
  • When a solution of salt (sodium chloride) in water is treated with a silver nitrate solution, a white precipitate forms immediately.  Help ?

    When a solution of salt (sodium chloride) in water is treated with a silver nitrate solution, a white precipitate forms immediately. When tetrachloromethane is shaken with aqueous silver nitrate, no such precipitate is produced. Explain these facts in terms of the types of bonds present in the two chlorides.

    1 AnswerChemistry7 months ago
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    Simple Anatomy of lumbar plexus question on terminology ?

    What do they mean by "in the substance of psoas muscle" here ?

    Medicine7 months ago
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    Quantum numbers MCQ help please?

    Is the answer here A or B 

    If its B, didn't 4s2 electrons fill first ? And would the n and l of all the transition metals in period 3 have the same value ?

    2 AnswersChemistry9 months ago
  • State functions and path functions chem?

    For some reason I can't seem to differentiate between these 2 terms.

    My book defines state function as

    'a property of a system that depends only on its present state, which is determined by variables such as temperature and pressure and which is independent of any previous history of the system.'

    What does that even mean ?

    Ive seen sources try to explain it using GPE as an analogy but what does that do to me when it comes to determining whether Pressure or volume are state functions are or not ?

    For context, I'm a first year uni student and this is from my general chemistry course.

    1 AnswerChemistry9 months ago
  • Ferromagnetism help please?

    "The strong, permanent magnetism seen in iron objects is called ferromagnetism and is due to the cooperative alignment of electron spins in many iron atoms. Paramagnetism is a much weaker effect. Nevertheless, paramagnetic substances can be attracted to a strong magnet. Liquid oxygen is composed of paramagnetic O2 molecules. When poured over a magnet, the liquid clings to the poles. "

    I don't understand what they mean by 'cooperative alignment of electron spins ' ?

    1 AnswerPhysics9 months ago
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    Probability distributions of electrons in the 3s subshell ?

    for the 2s orbital, there are 2 places to expect an electron in, one near the nucleus and one in a shell about it, but the latter is more probable, is that also the case for electrons in the 3s subshell ? Would it have 3 regions where electrons are likely to be found ? And would the outermost one of those have the highest probability ?

    Q2: You don't have to answer this but I don't really understand what they mean by contours here ?

    1 AnswerChemistry9 months ago
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    Can someone please help me solve these dynamic mcq's with weird pulleys?

    For question 22 I did 5g-12g(0.3)=14a

    for 23

    I don't know how to determine in which direction the friction will be acting

    And what are the forces acting on A ? There's its weight, and tension, and friction, but which coefficient of friction is do I use here ? and in which direction is it working ?

    Physics9 months ago
  • Multiple choice question on Translation and EPA sites -help please?

    The question is :

    During a normal translation cycle, Where would you expect to find t-RNA attached to a single amino acid ?

    options :

    1. E site

    2.P site

    3. A site

    4. both E and P sites

    5. both A and P sites

    I say 3 , but I'm not sure since you can find a single amino acid in P site too

    2 AnswersBiology9 months ago
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    Why isn't the pressure of the liquid uniform throughout?

    In this question , why isn't the pressure exerted by the air above the surface = to pressure down at the faucet ? I thought if an external pressure was applied on a liquid, it would spread throughout the

    entire thing.

    3 AnswersPhysics9 months ago
  • Archimedes and Buoyant force help please?

    The buoyant force is a result of difference in pressures at the edges of the immersed object  right ? 

    So if I immerse 2 objects with the same dimentions (so same volume) but very different densities 

    Would I get the same bouyant force ? 

    12 AnswersPhysics9 months ago
  • Gauge pressure vs Absolute help please?

    7. The weight of a car of mass 1.20 × 10^3 kg is supported equally by the four tires,

    which are inflated to the same gauge pressure. What gauge pressure in the tires is

    required so the area of contact of each tire with the road is 1.00 × 10^2 cm^2? (1 atm = 1.01

    × 10^5 Pa.)

    A) 11.6 × 10^5 Pa

    B) 11.6 × 10^4 Pa

    C) 2.94 × 10^5 Pa

    D) 2.94 × 10^4 Pa

    E) 2.94 × 10^3 Pa

    The answer is C according to my professor

    Here's my question, isn't that the absolute pressure ? 

    Isn't the total pressure exerted by the tires = to gauge pressure+atm ?

    By doing Force / 4A 

    aren't I getting the total pressure ?

    2 AnswersPhysics9 months ago
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    How much gamma ray photons does this lab technician absorb ?

    I'm confused about something here, the 2.9 mJ of energy that the body absorbed here, is more than the total energy it was subjected to (0.5 MeV), so is the 0.5 not the total energy ? Is it the energy/ 1 gamma photon ? And is that whats always given to us ? 

    So if they gave me the activity of a source in Ci, are they giving me the activity of 1 gamma photon ?

    2 AnswersPhysics9 months ago