Recent content by -_-'

  1. ?

    Object Must Be Placed at 15cm from Convex Mirror for Half Size Image

    A virtual image is formed by a convex mirror that has a 30cm focal length. Where must the object be placed if the image is to be half the size of the object? I know that since the mirror is convex F is negative (F is the focal length). Useful equations are 1/Do + 1/Di = 1/F, where Do is...
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    Solve Integrals: Getting the Approximated Area

    How did I do it? For those of you that are interested this is what i did: Well I was thinking about the properties of a quadratic equation and then it came to me...I have to square the x values to get a y value (I don't know how I got this wrong :blushing: maybe I was a little overwhelmed by...
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    Solve Integrals: Getting the Approximated Area

    Don't worry I figured it out...I was interpereting it wrongly, well actually the method I was using was wrong :blushing:. But its all good now :cool:. I worked it out my self :approve: yay! :smile: Now how did I get so confused on one of the easier questions...this always happens to me all the...
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    Solve Integrals: Getting the Approximated Area

    I think I'm on the wrong track some how :confused:
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    Solve Integrals: Getting the Approximated Area

    Studying integrals... I am studying for my maths B exam that is coming up and may need some help in understanding some concepts. Here is one question that i was getting some practise on but i got the wrong answer :eek:! Q: The area under the curve x²+ 1 between 1 and 4 is approximated by...
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    Calculate the derivative of: 8³√x

    cool thanks a lot :D
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    Calculate the derivative of: 8³√x

    i think its 8 times the cubed root of x
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    Calculate the derivative of: 8³√x

    I'm not sure how to calculate the derivative of: 8³√x :if anyone can help me or show me how to calculate the derivatives of similar problems such as this it would be greatly appreciated. :biggrin: Thanks It says in the back of the book that the answer is: 8/3³√x¹¹ I have never done one...
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    What is the force on a wire in a magnetic field?

    Question: 1. a) what is the force per meter on a wire carrying a 9.80-A current when perpendicular to a 0.80-T magnetic field? b) What if the angle between the wire and the field is 45°? For part a) I know that F = ILB, where I is the current, L is the length of the wire and B is the size of...
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    Currents and magnetic fields in a coil

    thanks for that every little bit of info helps
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    Currents and magnetic fields in a coil

    these are the formulas I know: B=F/IL F=BIL sin @ B=kI/r B=2(pi)knI Where k is Amperes constant (2x10^-7NA^-2), L is the length of wire, I is the current, r is the radius of the wire (but in some cases the distance between wires), and F is the force. Here's another diagram with...
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    Currents and magnetic fields in a coil

    Please help me if you can... question: Use the following quantities to calculate the magnetic field strength of the horseshoe magnet. Mass of coil: 20 grams current in coil: 2.0 amps length of bottom of coil: 10cm angle coil makes with vertical: 30 degrees Hint: Equate magnetic...
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