Recent content by e to the i pi

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    Coefficient of Friction in an inclined plane

    I'm confused... Where did you get that formula from? And what is the 'frictional force'?
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    Coefficient of Friction in an inclined plane

    Oh right... 9.8m/s^2 = 98/10 = 49/5. My mistake. So 14√3 * 49/5 = 686√3 / 5 Newtons going perpendicular to the plane (downwards). And 14 * 49/5 = 686/5 Newtons going down the plane. How do I work it out from here? Would the formula F = ma help me? If I let F = 686/5 and m = 28, then: a = F/m so...
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    Coefficient of Friction in an inclined plane

    So 14√3 * 49/10 = 343√3 / 5 Newtons going perpendicular to the plane (downwards). And 14 * 49/10 = 343/5 Newtons going down the plane. How do I work it out from here? Would the formula F = ma help me? If I let F = 343/5 and m = 28, then: a = F/m so a = (343/5) / 28 a = (343/140) a =...
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    Coefficient of Friction in an inclined plane

    1. A box of mass 28 kilograms is held at rest on a rough plane inclined at an angle of 60° to the horizontal by a rope attached to a vertical pole. When the rope is cut the box moves down the plane with an acceleration of a m/s^2. Find the expression for the coefficient of friction µ, in terms...
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    Solid of Revolution of an arcsin graph

    It's been almost a month and I still haven't solved it! Please help me!
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    Solid of Revolution of an arcsin graph

    Please tell me if I'm doing it right or wrong because I am still confused!
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    Solid of Revolution of an arcsin graph

    Okay, my new attempt at the solution is to use the formula: V = Integral from a to b of [f(y)]^2 * dy By transposition we get: x = sqrt((sin(y) + 1) / 2) Since x = f(y), then [f(y)]^2 = (sin(y) + 1) / 2 Now I thought that since an arcsin graph is symmetrical, I can just simply calculate it...
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    What is the difference between an 'increasing gradient' and a positive gradient?

    If the gradient of the gradient is positive, then it is an increasing gradient. Do you know how to check for that?
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    Solid of Revolution of an arcsin graph

    Please someone help me! It's been literally weeks and I still can't solve this problem :(
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    Solid of Revolution of an arcsin graph

    You said I should cut it in half and then calculate half of that. Does that mean I am only going from 0 to +pi/2 or from -pi/2 to 0, rather than the full way? So would the integral be like this: Integral from 0 to +pi/2 of: (sqrt((sin(x) + 1)/2)) * dx Is that the answer?
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    Solid of Revolution of an arcsin graph

    So once I have it in the form x = sqrt((sin(y) + 1)/2), do I then have to change the numbers on the top and bottom of the integral? So instead of going from -1 to 1, I am now going from -pi/2 to +pi/2? And by doing that, I am now wrapping it around the x-axis? So I can change it to become: y =...
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    Solid of Revolution of an arcsin graph

    1. Consider the function f(x) = arcsin(2x^2 - 1). Write down, but do not attempt to solve, a definite integral in terms of y, which when evaluated will give the volume of the solid of revolution formed by rotating the graph about the y-axis. 2. Endpoints are at (-1, pi/2) and (1, pi/2)...
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    Converting Position Vector vs Time to Cartesian Coordinates

    Thanks a lot for your help, dynamicsolo and SteamKing. Now I know how to solve these types of problems for the future. I let x = the value that is being multiplied by i and y = the value that is being multiplied by j and then ignore the r. Then I express y in terms of the value being multiplied...
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    Converting Position Vector vs Time to Cartesian Coordinates

    cos(2t) = 1 - 2(sin(t))^2 So r = sin(t)*i + (1 - 2(sin(t))^2)*j But I'm still confused because I don't know how to get rid of the i's and j's... Wait I think I get it: x = sin(t) y = 1 - 2(sin(t))^2 y = 1 - 2x^2 Is that right?
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    Converting Position Vector vs Time to Cartesian Coordinates

    1. The position vector of a particle at time t ≥ 0 is given by r = sin(t)*i + cos(2t)*j. Find the cartesian equation for the path of the particle. 2. I was told that the answer is: y = 1 - 2x^2 But I don't know how to obtain that solution. 3. r = sin(t)*i + cos(2t)*j At first I...