Search results

  1. F

    Semantics question about this angular momentum problem

    Wow, I wish i had caught that. Thanks!
  2. F

    Semantics question about this angular momentum problem

    Homework Statement Heading straight toward the summit of Pikes Peak, an airplane of mass 12,000 kg flies over the plains of Kansas at nearly constant altitude 4.30 km with constant velocity 175 m/s west. a) What is the airplane's vector angular momentum relative to a wheat farmer on the ground...
  3. F

    Help with multiple choice question (kinetic energy)

    oh right. the object could be moving at constant speed and a force could act against it and slow down its speed. thanks!
  4. F

    Help with multiple choice question (kinetic energy)

    ok so basically: the work changed the velocity and also changed the object's mass so that KE will remain the same but the internal energy changed so the energy of the object changed. the velocity has to increase since there is nothing in space that can counter the object's motion. if the...
  5. F

    Help with multiple choice question (kinetic energy)

    No friction would occur since the two objects would just move through space as if they were one object... Also what about random space particles. would they cause a small amount of friction if they slide past the object? If I'm understanding what you're saying correctly, you're saying that...
  6. F

    Help with multiple choice question (kinetic energy)

    The work caused a change (either positive or negative) in the bodies internal energy? Also if some other object exerted a force on the body and slid against it, that would cause friction in space right?
  7. F

    Help with multiple choice question (kinetic energy)

    Homework Statement Work is done on an object far out in space where it has negligible gravitational-PE. If in the process there is no net change in KE, we can conclude a) friction may have been operative b) this situation is impossible c) the energy of the object has decreased d) the...
  8. F

    What are the amplitudes called for blue visible light, and microwaves?

    The amplitude of sound waves is commonly referred to as volume. What about for blue visible light, and microwaves? I'm guessing for the first one it's brightness. Btw I'm looking for a word answer, not the magnitude of the amplitude (not a numerical amplitude) Thanks for reading.
  9. F

    About the equation for net work done by nonconservative forces

    Wnc = delta (kinetic energy) + delta(potential energy) (Work done by nonconservative forces) = (change in kinetic energy) + (change in potential energy) Now, my professor gave us this formula instead of the one above: W - H = (change in kinetic energy) + (change in potential energy)...
  10. F

    Conceptual question about angular speed and radius for rotational motion

    Thanks. Btw, i will only look like a muppet if someone is looking.
  11. F

    Conceptual question about angular speed and radius for rotational motion

    so angular speed is dependent on radius since the force that moves the wheel would cause a greater acceleration if the wheel had a smaller radius (meaning it would be a smaller wheel)? also assuming the force that moves the wheel stays constant.
  12. F

    Conceptual question about angular speed and radius for rotational motion

    let's say a wheel rotates with a constant angular acceleration. Would its angular speed be affected if the radius was changed? It seems that angular speed would be independent of the radius since the angle is just a proportional quantity.
  13. F

    About ideal mechanical advantage for an inclined plane

    Yeah, that's what I guessed at...so in this case the IMA and AMA would just be 1? since there wouldn't be any advantage or disadvantage to using a machine to drag the object across the surface?
  14. F

    About ideal mechanical advantage for an inclined plane

    the formula for the IMA for an inclined plane is 1/sin(theta)...right? But what if the angle was zero (which would mean it is not an inclined plane), then you wouldn't be able to divide by zero...so how would you get the IMA if the angle was zero? I am very very confused about this...any help...
  15. F

    How can tension be the same along all points in a rope?

    Consider the following problem: The distance between two telephone poles is 50.0 m. When a 1.00-kg bird lands on the telephone wire midway between the poles, the wire sags 0.200 m. How much tension does the bird produce in the wire? Ignore the weight of the wire. The tension is 613 N. But...
  16. F

    Does static friction cause a car to move forward?

    Ok, I think i understand it a little better... how about when someone is pulling an object, such as a box, along a surface...is the static friction from the ground an actual reaction force to the force exerted by the person on the box? as in, is it part of the action-reaction pair, with the...
  17. F

    Does static friction cause a car to move forward?

    I get that when a car moves forward, its tires are rotating backwards, but the static friction from the ground, as a reaction force to the force from the tires, prevents the tires from moving backwards (not sure on this). So does the static friction only prevent the tires from moving backwards...
  18. F

    The exact definition of tension

    Thanks stewart, that cleared it up...I think.
  19. F

    The exact definition of tension

    When people refer to the tension in a rope, string, etc...are they referring to the magnitude of the tensile force? But isn't tension a vector. So tension in general is a vector, but when referring to the tension in a rope they are talking about the magnitude? Please clarify.. edit: btw...
  20. F

    A basic rope tension problem

    Upon further research I discovered that in a tug of war situation the force exerted by both ends are the same...so I guess that's why my question didnt make sense... Though I don't really see how that's possible.. if a person was stronger than the other person at the other end of the rope...
  21. F

    A basic rope tension problem

    Actually I made up the problem myself in an attempt to understand tension...let's say the rope has no mass, why wouldn't it make any sense? I'm just basing it off the concept of the same problem, except the forces are both 5 N, the rope has no mass, which means, according to my textbook, that...
  22. F

    A basic rope tension problem

    Homework Statement If a rope were being pulled in opposite directions with two opposing forces, one being 5 N and the other 7 N, what is the tension of the rope? Homework Equations The Attempt at a Solution Since the rope would be accelerating in the direction of the force of 7 N, the...
Top