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    Easy question calculating uncertainty

    Homework Statement What is the mass uncertainty, \deltam = m+ - m, of the particle? Homework Equations m = \frac{R*|q|*B}{v} where R = (6.4\pm0.1) cm (convert to meters so 0.064\pm0.001) |q| = 1.6*10-19 B = (2.50\pm0.02) T v = (5.25\pm0.04)x107 The Attempt at a Solution I...
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    Amplitude & Time constant

    Homework Statement A gust of wind hits a flagpole and starts it oscillating. After 10 s, the amplitude of its motion has decreased to 25% of its initial value. What is the value of the time constant? Homework Equations xmax(t) = Ae-t/\tau The Attempt at a Solution I know...
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    Walking away from two loudspeakers-destructive interference

    I am working on the same problem, I don't understand what to do for post #10 and beyond. Can someone please help me!
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    Determing wavelength of sound wave from steel string

    Speed of wave in string: v = \sqrt{\frac{T_s}{\mu}} Ts = 100N \mu = 0.0012kg/m v = 288.7 Fundamental Frequency: F0 = \frac{v}{\lambda_0} \lambda0 = 2L = 2*1.2 \lambda0 = 2.4 f0 = \frac{\sqrt{\frac{T_s}{\mu}}}{2L} In the air: \lambda = \frac{v}{f_0} \lambda =...
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    Determing wavelength of sound wave from steel string

    Homework Statement A 120 cm-long steel string with a linear density of 1.2 g/m is under 100 N tension. It is plucked and vibrates at its fundamental frequency. What is the wavelength of the sound wave that reaches your ear in a 20 \circC room? Homework Equations Fundamental...
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    Finding gravity on Planet X from a string, a weight, and frequency

    Homework Statement Astronauts visiting Planet X have a 2.5 m-long string whose mass is 5.0 g. They tie the string to a support, stretch it horizontally over a pulley 1.8 m away, and hang a 1.3 kg mass on the free end. Then the astronauts begin to excite standing waves on the string. Their...
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    Calculate DILATED LIFETIME of muon traveling close to speed of light

    I replaced the numerator Delta t0 with the proper lifetime. My answer is 2.599 x 10-5 seconds. Is this correct??
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    Calculate KINETIC ENERGY of proton traveling close to speed of light

    O should I be using the equation: K =( g - 1 )MC2 or K= (1/2)gMV2 ? What is the correct formula for calculating kinetic energy when a particle's speed approaches the speed of light??
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    Calculate INERTIAL MASS of proton traveling close to speed of light

    Homework Statement A proton is traveling with a speed of v = 2.993x108 m/s. Calculate the value of the inertial mass for this proton. Assume that the speed of light is c = 3.000 x 108 m/s and that the mass of the proton is 1.673 x 10-27 kg. Note: Do your calculations to 4 significant...
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    Calculate KINETIC ENERGY of proton traveling close to speed of light

    Homework Statement A proton is traveling with a speed of v = 2.990x108 m/s. Calculate the (relativistically correct) value of the kinetic energy for this proton. Assume that the speed of light is c = 3.000 x 108 m/s and that the mass of the proton is 1.673 x 10-27 kg. Note: Do your...
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    Calculate DILATED LIFETIME of muon traveling close to speed of light

    Homework Statement A muon is traveling with a speed of v = 2.995x10^8 m/s. Calculate the value of the dilated lifetime for this muon. Assume that the speed of light is c = 3.000 x 108 m/s and that the proper lifetime of the muon is 1.500 x 10-6 s. Note: Do your calculations to 4...
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    Trumpet players, sound intensity level

    Homework Statement Five trumpet players have a sound intensity level of 75dB. What would be the sound intensity level of 30 such trumpet players? _______dB Homework Equations Increasing the sound intensity by a factor of 10 results in an increase in perceived loudness by approx. a...
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    This is SO simple, why can't I figure it out?

    This is SO simple, why can't I figure it out?? I need to figure out the length of 2 strings and L1+L2 = 4 I get to the point, using other parts of the problem that are not pertinent to this, of: 1.11L2 + L2 = 4 The answer is L2 = 1.9 HOW in the world does L2 work out to be 1.9? How...
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    Medical Weird eye viewing effect

    Were you taking any sort of cold medicine or remedies? Any other symptoms before or after this event occurred? Did you have a true migraine later that day?
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    Molar Volume and Molal Volume

    Molarity (in units of mol/L, molar, or M) or molar concentration denotes the number of moles of a given substance per liter of solution. (Wiki) Molality (mol/kg, molal, or m) denotes the number of moles of solute per kilogram of solvent (not solution). (Wiki) What are the details of the problem?
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    Oscillation, Frequency, Amplitude etc Hmwk Problem

    Thank you, I was able out to figure out the problem last night by following a post on yahoo. I want to post it step by step here for other stumped students: Part B. Determine the amplitude. w = 2(pi)f w = 2(pi)(2.0Hz) w = 12.6 rad/sec v = w Sqrt(A2-x2) -0.30 = (12.6rad/sec) Sqrt[ (A2)...
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    Another amplitude and oscillation problem

    Homework Statement A small earthquake starts a lamppost vibrating back and forth. The amplitude of the vibration of the top of the lamppost is 6.5 cm at the moment the quake stops, and 8.0 seconds later it is 1.8 cm. A. What is the time constant for the damping of the oscillation? _____...
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    Oscillation, Frequency, Amplitude etc Hmwk Problem

    Homework Statement A 200g mass attached to a horrizontal spring oscillates at a frequency of 2.0 Hz. At one instant, the mass is at x=5.0cm and has vx = -30cm/s. A. Determine the period. T= ____seconds B. Determine the amplitude. A =____cm C. Determine the maximum speed. vmax =...
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    Need Hmwk Help . Fluid mechanics, Fluids in Motion, Pressure

    The answer is 3200 Pa. However, I do not know how to arrive at that solution. I'd reallllyyyyy appreciate it if someone could walk me through it, step by step.
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    Need MORE Hmwk help . Fluid mechanics, Fluids in motion, pressure

    I was not able to get the answer before my assignment was due, the answer was 8.2E5 Pa. But thank you, I really appreciate your help.
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    Need MORE Hmwk help . Fluid mechanics, Fluids in motion, pressure

    What do you mean by gauge pressure is relative to P? Do you think that I am on the right track with the progress I've made? P1=P2+49806
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    Need MORE Hmwk help . Fluid mechanics, Fluids in motion, pressure

    Correct, a numerical value in Pascals. I think I need to incorporate the length of each section as well, not sure how though.
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    Need MORE Hmwk help . Fluid mechanics, Fluids in motion, pressure

    Thank you so much for replying! So I plugged in everything that I calculated so far and ended up with: P1 = P2 +49805 I can't figure out how to find the pressure in the smaller diameter tube so I can plug that in. I know it should be easy...I have the flow rate and the diameter, but I'm stuck...
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    Need MORE Hmwk help . Fluid mechanics, Fluids in motion, pressure

    College Physics Homework Statement The figure shows a section of a long tube that narrows near its open end to a diameter of 1.0mm. Water at 20celsius flows out of the open end at 0.020 L/s What is the gauge pressure at point P, where the diameter is 4.0mm...
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    Need Hmwk Help . Fluid mechanics, Fluids in Motion, Pressure

    College Physics Homework Statement The figure shows a syringe with a 4.0-cm-long needle, filled with water at 20celsius. What is the gauge pressure of the water at the point P, where the needle meets the wider chamber of the syringe...
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