Recent content by Andy21

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    Is the torque of a couple equal to the resultant torque?

    This question is part of my homework. I am asking if the resultant torque in a system is equal to the sum of all of the torques or moments of the forces such as those from couples or from individual forces in the system.
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    Is the torque of a couple equal to the resultant torque?

    Homework Statement If the only forces acting in a system are a couple, will the torque of the couple be the resultant torque of the sytem? Homework Equations The Attempt at a Solution
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    Do couples always produce rotation?

    So if there are no other forces acting, only the couple, will the torque of the couple equal the resultant torque?
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    Do couples always produce rotation?

    Homework Statement Do couples always produce rotation and does the torque of a couple always equal of resultant torque? Homework Equations The Attempt at a Solution I think the answer for both of them is yes.
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    Resultant force on aircraft door

    thanks for the help
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    Resultant force on aircraft door

    Homework Statement The air pressure at the altitude an aircraft is flying at is 28kPa. If the pressure inside the cabin is maintained at 100kPa, what is the resultant force on a door of area 2m^2 in the side of the aircraft? Homework Equations The Attempt at a Solution I am not...
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    Why Is There Only One Stationary Point for the Volume of This Box?

    Thanks for the help
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    Why Is There Only One Stationary Point for the Volume of This Box?

    I got a volume of -486 for x=9 and 200 for x=2. I think that the one stationary point must be at x=2 because a box can't have a negative volume. Is this correct?
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    Why Is There Only One Stationary Point for the Volume of This Box?

    Homework Statement The volume of a box is given by V=4x^3 -66x^2 +216x. Explain why there is only one value of x for which V is stationary? Homework Equations The Attempt at a Solution dV/dx = 12x^2 -132x +216 at a stationary point x^2-11x+18=0 so x=2 or 9
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    Circle Geom: Show Line Tangent & Find Point of Contact

    Homework Statement Show that the line 2x+3y=27 is a tangent to the circle with centre (4,2) and radius sqrt of 13. Find the co-ordinates of the point of contact. (Without a calculator) Homework Equations The Attempt at a Solution I have worked out that the equation of the circle...
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    How do you convert from one line equation to another?

    Yes sorry, what I asked in the original question was wrong. Can you explain how to get the answer 4x+y-6=0 for the equation of the tangent from the circle equation and the point I gave in my previous reply. Thanks.
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    How do you convert from one line equation to another?

    Thanks for the help. The reason I asked this question is to find the equation of the tangent to the circle (x+3)^2 + (y-1)^2=17 at the point (1,2). I know the answer to this is 4x+y-6=0. Can you explain to me how to get this answer.
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    How do you convert from one line equation to another?

    Homework Statement Show how the equation of a line y-2=4x-4 can be converted into the equivalent line equation of 4x+y-6=0. Homework Equations The Attempt at a Solution The closest I have got to it is 4x-y-2=0 by adding and subtracting terms to both sides.
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    Does the acceleration of free fall take air resistance into account?

    I think it doesn't and that the acceleration of free fall is assuming the Earth was in a vacuum. I wanted to check.
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    Does the acceleration of free fall take air resistance into account?

    Homework Statement Does the acceleration of free fall take the effect of air resistance into account or is it equal to the acceleration of free fall on Earth if the Earth was in a vacuum? Thanks Homework Equations The Attempt at a Solution