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  1. J

    Flynn's Taxonomy as a modern classification

    Flynn's Taxonomy was a classification of computer architectures published in 1966. Computing has changed a lot since then. Is this taxonomy still useful? What are some of its shortcomings for evaluating modern computing systems?
  2. J

    185 stored as a signed 8-bit number?

    Several exercises in my textbook start with assumptions that confuse me. For example: Assume 185 and 122 are signed 8-bit decimal integers stored in sign-magnitude format. Assume 151 and 214 are signed 8-bit decimal integers stored in two's complement format. I am then to go on to find the...
  3. J

    Engineering Op-amp resister circuit analysis

    Homework Statement Given the ideal op-amp, determine the resistor R2 and the current I2 where Vin=500mV, Vout = 2.5 V, and R1=5kV. Homework Equations No current passes through op-amps, the op-amp tries to make V+ and V- equal. Ohm's law, voltage divider equation The Attempt at a Solution...
  4. J

    Low pass filter: cutoff and peak output

    Homework Statement (a) If R1 = 4.7kΩ, what value for C1 will give a cutoff frequency of 50kHz? (b) If the input voltage is described by the equation Vin = 3cos(2π(4000)t), what will the peak output voltage be?[/B] Homework Equations (a) fc = 1/(2πRC) (b) Vout/Vin = 1/√(1 + (2πfRC)2) The...
  5. J

    Ideal opamp analysis

    Given this ideal op-amp, determine Vout if Vin = 2V and Vs = 15 V. So I know that the ideal op-amp has infinite gain. As the difference between V+ and V- is substantial (2V), wouldn't that mean the output would theoretically by infinitely large but instead max out at Vs? Am I understanding...
  6. J

    RMS in AC circuits

    Why do we use the square of the graph as opposed to the absolute value of the graph to find the mean values?
  7. J

    Wire and resistor in parallel

    If a "normal" looking wire and a resistor are in parallel on a simple circuit diagram, will any current pass through the resistor?
  8. J

    Engineering Multi-loop circuit

    ΩHomework Statement In the following circuit, what is the current across the R2 resistor? V1 = 1.5 V, V2 = 1.5 V, R1 = 470 Ω, R2 = 560 Ω Homework Equations Kirchhoff's laws The Attempt at a Solution I attempted to create a system of equations with the intention of finding R2, as was...
  9. J

    Engineering I thought circuits had to be closed

    Homework Statement I am supposed to determine the potential differences between the points. However, I thought circuits had to be closed...
  10. J

    Maximum resistance and power for LED

    Homework Statement You wish to use an LED (D1) which provides essentially zero resistance and is rated to accept either a maximum of 75 mW of power or 30 mA of current. In the following two circuits, what range values for resistor R1 will be acceptable in each case if the voltage provided by V1...
  11. J

    Young's Modulus, Bulk Modulus, and Shear

    I'm dealing with a cylinder. The equation for the stress of each is Force / Area. What are the different areas for the equation in regard to young's modulus, bulk modulus, and shear modulus? Is the area Young's Modulus stress the area of circle face? What about for shear stress? Would the...
  12. J

    Force with regard to 0 acceleration

    Premise: Ball A is accelerated on a level, frictionless plane until it reaches a velocity of 5 m/s. Ball A travels at 0 acceleration until it collides with Ball B. Statements: 1. According to F = ma , Ball A cannot produce a force at 0 acceleration. 2. Upon collision, Ball A applies a force...
  13. J

    Putting a Compass in a Magnetic Field

    Homework Statement If you put a compass in a magnetic field, the compass will... a) seek electrical charge concentrations. b) line up in a direction perpendicular to the magnetic field lines. c) swing randomly. d) line up in a direction parallel to the magnetic field lines. Which one is it...
  14. J

    Finding electromotive force

    Homework Statement A battery has a current of 3.0A flow through it. It has an internal resistance of 0.039Ω and the circuit has a load of 45Ω. a) What is the emf? b) What is the voltage that flows? Homework Equations V = ε - IR The Attempt at a Solution ε = V + IR ε = (45Ω)(3A) + (3A)(0.039Ω)...
  15. J

    Leads in electrical circuit

    A branch of multi-level parallel circuit has 6 leads coming into it and currents of 3 A, 4.4 A, and 8.8 A flow into it, and one of the leads has a current flowing out of it of 6 A. If the other two leads have identical currents flowing out through them, what are those currents? Any help would...
  16. J

    Finding electric field between two charges

    Homework Statement Two charges, Q1 = 4*10-8 and Q2 = 2.7*10-8 are 3.25 m apart. What is the electric field magnitude halfway between them? Homework Equations E = kQ/r2 The Attempt at a Solution E1= k (4*10-8C)/(1.63m)2 = 135 N/C E2= k (2.7*10-8C)/(1.63m)2 = 91.4 N/C 135 N/C - 91.4 N/C = 43.5...
  17. J

    Electrical and gravitational forces of protons

    Homework Statement At what distance between two protons are the electrical and gravitational forces equal? Homework Equations electromagnetic Force = k(Q1*Q2/r^2) gravitational Force = G(m1*m2/r^2) Constants: k = 9.0*10^9 (N m^2/c^2) G = 6.673 × 10^-11 (m^3 kg^-1 s^-2) Charge of proton...
  18. J

    Center of gravity

    Homework Statement If Bethany and Serendipity each exert a force of 350 N on each arm of a wheelbarrow with 1.25 m arms and carry Cardinal Glick in the bucket, who has a weight of 1,050 N, where is the center of gravity of the bucket and the Cardinal with respect to the wheel? Pointers would...
  19. J

    Probability using box and whisker

    The question: A box and whisker plot is made from the lengths of 39 salmon. No two lengths are the same. Two of the salmon are picked at random. What is the probability that they will both be longer than the lower quartile value. My solution: x x x x x x x x x x x x x x x x x x x x x x x x x x...
  20. J

    Finding Rotational Kinetic Energy of Sphere on Ramp

    Homework Statement If Inga, the Laboratory Assistant, rolls a spare head down a 4 m ramp because it was spherical and solid and too heavy at 4.5 kg at a speed of 4.5 m/s, what was its total kinetic energy? Homework Equations KE = (1/2) I ω^2 I = (2/5) MR^2 The Attempt at a Solution...
  21. J

    Radius of Orbit given Period

    Homework Statement If a new planet has a year of 3.44578 Earth years, what is its radius of orbit in meters if Earth's orbital radius is 149,597,870,700 meters? Formula: r = (vt)/(2pi) How can I use this without velocity? All help is appreciated as I'm not sure how to go about this...
  22. J

    Tension in vertical circular motion

    Homework Statement If you are spinning an object of mass 3.25 kg on a 0.8 m long chain at 20 rpm (vertical cirular motion), a) what is the tension at the top b) 43° from the top and c) at the bottom? Homework Equations String tension: T = Fc - mg cosθ Tension at top: T = (mv^2/r) - mg Tension...
  23. J

    Acceleration given Earth's radius

    Given that the Earth has a radius of 6.4x10^6 m, what is the acceleration of a Trojan Badger launched from a catapult when it is 8.5x10^8 m above the surface of the Earth? I'm not sure how to go about this question. All help is appreciated: formulas, explanations, answers, etc.
  24. J

    Force Needed to Hold Rocket Down

    Q: The motors of a 1,000 kg rocket standing vertically on the ground are being tested. Fuel is being burned at the rate of 5.0 kg/s with an exhaust speed of 2.8 km/s. Find the force needed to hold the rocket down. Attempt: I'm not really sure how to go about this question. I've thought about...
  25. J

    Finding work with given horsepower

    Homework Statement If one ferretpower (fp, made-up unit) is equal to 0.0312 hp, and an electric motor puts out 2.75 x 10^5 fp, how high (in meters) can it lift a crate that has a mass of 2.75 slugs in 5 s? Homework Equations P = W/t W = mgh 1 hp = 745.7 watts 1 slug = 14.59 kg The...
  26. J

    Average force applied by bullet

    Homework Statement What is the average force applied by a 75 g bullet that leaves a gun at 1350 m/s and hits a target 75m from the barrel of the gun? Homework Equations F = ma The Attempt at a Solution First I had the equation F = ma, and began filling in all the variables I could...
  27. J

    Pulley, friction, acceleration

    Homework Statement http://imageshack.us/a/img703/7864/physicsb.png [Broken] From the image above: a) If there is no friction between A and surface, what is the blocks' acceleration? b) With coefficient of 0.2?
  28. J

    Box sliding on 35 degree grade

    A box slides down a frictionless plane that makes an angle of 35 degrees with the horizontal. A horizontal force of half the box's weight presses the box against the plane. What is the box's acceleration? I'm confused as to what kind of effect would a horizontal force have on an object...
  29. J

    Overcoming static friction - easy

    Homework Statement A very strong 100kg man is having a tug of war with a 1500 kg elephant. The coefficient of static friction for both on the ground is 1.0. a) Find the force needed to move the elephant. b) What would happen if the man could actually exert such a force? Homework Equations Ff =...
  30. J

    Force on resting ball

    Homework Statement View the file below. Disregarding friction, how much force does each board of wood put on the 100 N ball? http://desmond.imageshack.us/Himg841/scaled.php?server=841&filename=physcis.jpg&res=landing [Broken]
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