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    Specific Rotation Problem

    Thanks, hmmm..im not sure if we're expected to make some assumptions but that's how the Question was worded exactly.
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    Specific Rotation Problem

    Homework Statement The specific rotation of a tetrasaccharide was measured to be -20.5°. Upon complete hydrolysis in acid the optical rotation of the solution was found to be -36.9°. Knowing that the specific rotations of n-acetylgalacosamine,3-deoxy-l-fucose and 2-deoxy-D-ribose are...
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    Ionic exchange

    Homework Statement 10 mL solution of 0.5 M CrCl(OH2)52+ is allowed to aquate to Cr(OH2)63+. To determine an approximate rate of reaction, the amounts of CrCl(OH2)52+ and Cr(OH2)63+ present after a certain period of time are evaluated. This is done by pouring the solution on a cation exchange...
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    Calculate molar conductivity of Co(NH3)4CO3]NO3?

    Homework Statement This was determined from an experiment,where the resistance of 0.02M of KCl was to be determined [KCl]=0.02M conductance=2.86ms L=0.002768ohm^-1 to obtain k Co(NH3)4CO3]NO3 : conductance: 1.923ms concentration of cobalt complex: 0.002M Homework Equations k=RL...
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    Helium atom and bohr model

    should i use this ΔE = RchZ²{1/n²(1) - 1/n²(2)} where R is the Rydberg constant (1.0974 x 10E7 m-¹); c the speed of light in vacuum (2.9979 x 10E8 m s-¹); h Planck's constant (6.626 x 10E-34 J s); Z nuclear charge; n(1) & n(2) are the principal quantum numbers of the electron transition
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    Helium atom and bohr model

    Homework Statement He+ ion consists of a nucleus which is an alpha particle plus one orbiting electron.Hence it has a net positive charge. a)Derive an expression for the electron state energies b)what is the wavelength associated with a transition between the lowest two energy states...
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    Constructive Interference of Sound waves

    i think r is suppose to represent distance. The question gives me the formula in terms of r I guess my question is if my calculations are correct? Not sure if im on the right track. Im not sure how many answers to give I wasnt told but I calculated up to 3.
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    Constructive Interference of Sound waves

    Homework Statement A pair of speakers connected to the same signal generator face each other, one at x=0 and the other at x=1.5m. If they are producing a sound frequency of 2000Hz what are the points (position x) of constructive interference between the speakers? Express your answer in...
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    Magnetic field of earth, how much current needed to cancel it

    Homework Statement Solenoid consists of a hollow tube of length 5 meters and around which 1000 turns of wire are wrapped.? Current I flowing in the wire generates a magnetic field whose direction is given by the right hand rule. It can be shown the magnetic field in a long narrow tube is...
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    Doppler effect

    Homework Statement Man travels down the highway in his car whistling middle C A policeman has a defective radar gun but passed a physics course. He hears the pitch change from D(294 Hz) immediately above middle C(262Hz) to A#(233Hz) immediately below middle C as the car passes. a) How fast...
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    Waves of sound from singer

    lol well i have a sheet we got with all the notes and frequency so i dont think were expected to memorize them, anyways thanks i feel like this is going no where ill just ask my professor
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    Waves of sound from singer

    from here not sure which octave anyways i think its wrong the answer should still be C http://www.sengpielaudio.com/calculator-… [Broken] Scroll down to "Frequency to Musical Note Converter".
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    Waves of sound from singer

    so 2.7 x 262hz=707hz so thats F5 note ?
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    Waves of sound from singer

    those are the same values i just researched to get more accurate values
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    Waves of sound from singer

    927 is the speed of helium and 343 is the speed of sound
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    Waves of sound from singer

    Wavelength in helium λ = c / f = 927 / 262 = 3.538 m. Wavelength in air λ = c / f = 343 / 262 = 1.309 m. Ratio = 3.538 / 1.309 = 2.7
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    Waves of sound from singer

    233Hz/294Hz=0.80 which is less than the wavelength ratio
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    Waves of sound from singer

    oh okay im just trying to do it the way my teacher did but the ratio is 132cm/65.9cm=2
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    Waves of sound from singer

    okay this is what i did f=velocity of air/lambda middle C 262Hz=330m/s / lambda middle C which gives lamba=1.2595 m frequency of helium is f=velocity of helium/lambda f=965m/s/1.2595m f=766Hz
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    Waves of sound from singer

    the steps i did before is what my teacher did, he just solved it halfway and said thats the equation we use, so im a bit confused because i calculated it to be 766Hz which is around the note G and then after some research i found that the note is still C but i guess a few octaves higher? not...
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    Waves of sound from singer

    Homework Statement Singer sings middle C. She then gulps helium and tries to sing the same note i.e her vocal chords remain the same. What note will the listener hear? Homework Equations f=velocity of air/lambda middle C The Attempt at a Solution f=velocity of air/lambda...
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    Damped oscillations

    so time is independent
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    Damped oscillations

    Homework Statement Does the time for one oscillation, change during the damped oscillations? and please explain Homework Equations The Attempt at a Solution
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    Finding vector perpendicular to other vectors

    okay so i think its the cross product and when i do it i get (2,-4,2), is that all? or is there something more
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    Finding vector perpendicular to other vectors

    like the dot product? sorry i havent done vectors in 2 years so im rusty
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    Finding vector perpendicular to other vectors

    Find vector having unit length perpendicular to both x and y. x=(1,2,3) and y=(-1,0,1)? im not sure where to begin
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    Velocity problems

    for the first one i used v=at i got (5,10,15)m/s the third part i used d=1/2at^2 im not sure how to find the distance travelled in 5 seconds
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    Velocity problems regarding vectors

    Homework Statement Spaceship initially at rest as measured,experiences constant acceleration of a=(1,2,3)m/s^2? what is the velocity,after 5 seconds, and speed after 5 seconds and position after 5 secs what is the distance it has travelled in 5secs Homework Equations v=at not...
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    Velocity problems

    Spaceship initially at rest as measured,experiences constant acceleration of a=(1,2,3)m/s^2? what is the velocity,after 5 seconds, and speed after 5 seconds and position after 5 secs what is the distance it has travelled in 5secs
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    Finding xy coordinates of obtuse and acute triangle

    This might seem easy, but im sort of rusty on the math since i havent taken a math course in a while. Homework Statement A 2 meter long bar lies in the xy plane with one end at the origin. find position at the xy plane of the other? end point of the bar if the angle the bar makes with the...
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