Search results

  1. C

    Height of sign?

    thanks for all your help, what, do you have to be regular around here to get some answers.
  2. C

    Height of sign?

    really, no one has any help?
  3. C

    Height of sign?

    nobody?? C'mon guys I need some help.
  4. C

    Height of sign?

    ok so I've changed somethings. I'm letting a represent the height of the building and h represent the height of the sign and theta represent the angle of vision between the top and bottom of the building, x represents the distance away from the building, which is 60 ft and beta which is the...
  5. C

    Height of sign?

    At the top of their 50 foot tall sales building, there is a 10 feet tall sign. But he wants to replace it with a sign for which the ideal viewing distance is 60 feet from the building. For an observer, the angle between the lines of sight from the observer's eye to the top and the bottom of the...
  6. C

    Project help

    Homework Statement You work for MOONOCO, an oil company that has a drilling platform one mile due north of a long straight shoreline that goes east and west. MOONOCO has three storage depots on land. The first (Depot Alpha) is on the shoreline four miles west of the nearest point on shore to...
  7. C

    Is there a number that is exactly one more than its cube?

    is there a number that is exactly one more than its cube?
  8. C

    Flywheel help

    An electric motor turns a flywheel through a drive belt that joins a pulley on the motor and a pulley of the flywheel. The flywheel has a mass of 80 kg and a diameter of 1.25m. Its pulley has a much smaller mass and a radius of .230m. the tension in the upper (taut) part of the belt is 135N and...
  9. C

    Collision help

    Two blocks are free to slide along a frictionless wooden track. A block of mass m1=5 kg is released from point A. Protruding from its front end is the north pole of a strong magnet, repelling the north pole of an identical magnet embedded in the back end of the block of mass m2=10 kg, initially...
  10. C

    How far does his center of mass move up

    Dave Johnson, the bronze medallist at the 1992 Olympic decathalon in Barcelona, leaves the ground at the high jump with vertical velocity component 6 m/s. How far does his center of mass move up as he makes the jump? I've got nothing for info how do I solve this?
  11. C

    Question about spring compression

    A 12 kg block slides from rest down frictionless 35 degree incline and is stopped by spring w/ constant of 3.00x10^4 N/m. The block slides 3 m from the point of release to the point of rest against spring, how far has spring compressed? Now I know this involves the equation Ws= 1/2kxmax2, but...
  12. C

    Work don by a spring problem

    ok I'm giving this a shot, I found a similar problem in my book. They show vf= the square root of 2W/m and to find W, they multiplied the force by delta x. So for this problem, I added both forces of the springs to get 5000 N/m and multiplied it by .5m to get 2500J. I then used the books...
  13. C

    Work don by a spring problem

    but how do I find inital speed, the equations are for work done, not initial speed.
  14. C

    Work don by a spring problem

    A 6000 kg freight car rolls along rails with negligble friction. The car is brought to rest by a combination of 2 coiled springs. Both obey Hooke's law with k1=1600 N/m and k2=3400 N/m. After the first spring compresses a distance of 30 cm, the second springs acts with the first to increase the...