Recent content by iamwilson

  1. I

    Examining Forces in a Symmetric Building

    Homework Statement A symmetric building has a roof sloping upward at 34.0 degrees above the horizontal on each side. A)If each side of the uniform roof weighs 1.10×10^4N , find the horizontal force that this roof exerts at the top of the wall, which tends to push out the walls...
  2. I

    Volume of Solid within Sphere and Outside Cone | Integration Homework Solution

    so i did as u said, i changed them to spherical polar, z=3psin(phi), but x^2+y^2+z^2=1, i don't know how to change that to shperical polar, could you please help me. the homework is due tomorrow and I've a test on that day too！ thanks!
  3. I

    Volume of Solid within Sphere and Outside Cone | Integration Homework Solution

    i also tried that way but how do i get phi though and theta
  4. I

    Volume of Solid within Sphere and Outside Cone | Integration Homework Solution

    Homework Statement FInd the volume of the solid that lies within the sphere x^2 + y^2 + z^2 = 1, above the xy plane, and outside the cone z = 3 \sqrt{x^2+y^2} Homework Equations The Attempt at a Solution i tried to use rdzdrd(theta) to integrate this question but i can't get it...
  5. I

    Double Integration in Polar Coordinates: Area Between Circles and Line y=7

    yes， i did, even ask my professor on how to doing it, but she only gave me the r=7+7cos(theta) but that doesn't make sense, i thought it's 14cos(theta), Dick, i completely loss, can anyone help me on this one
  6. I

    Evaluating Improper Integrals Using Polar Coordinates

    Homework Statement A.Using polar coordinates, evaluate the improper integral of e^(-10(x^2+y^2))dxdy B. use part A to integrate from negative infinity to positive infinity of e^(-10x^2)dx 2. Homework Equations [/b] The Attempt at a Solution i got part A to be pi/10, but for...
  7. I

    Double Integration in Polar Coordinates: Area Between Circles and Line y=7

    Homework Statement Using polar coordinates, evaluate the integral which gives the area which lies in the first quadrant below the line y=7,and between the circles x^2 + y^2 = 196 and x^2 - 14x + y^2 = 0. Homework Equations The Attempt at a Solution i tried to double integrate...
  8. I

    Angular acceleration of the disk as a function of time

    NVM, i figured it out
  9. I

    Angular acceleration of the disk as a function of time

    Homework Statement A disk of radius 21.0cm is free to turn about an axle perpendicular to it through its center. It has very thin but strong string wrapped around its rim, and the string is attached to a ball that is pulled tangentially away from the rim of the disk (the figure ). The pull...
  10. I

    Solving a Physics Homework Problem: Rocket Mass and Acceleration

    sorry, this is my first time using this website, so i don't know all the rules, but it's is extremely helpful
  11. I

    Rocket Mass & Accel: 6000kg, 25m/s2

    Homework Statement If the rocket has an initial mass of 6000kg and ejects gas at a relative velocity of magnitude 2000m/s , how much gas must it eject in the first second to have an initial acceleration of 25.0m/s^2 Homework Equations v=v_exln(m_0/m) The Attempt at a Solution i...
  12. I

    Solving a Physics Homework Problem: Rocket Mass and Acceleration

    A rocket is fired in deep space, where gravity is negligible If the rocket has an initial mass of 6000kg and ejects gas at a relative velocity of magnitude 2000m/s , how much gas must it eject in the first second to have an initial acceleration of 25.0m/s^2 ? im stuck on this problem, can...