Recent content by LeonhardEu

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    Research Fields in Theoretical Physics

    The time I will be asked to take a subject for my graduation project and I'm searching for something in hot fields for modern physics research. Unfortunately I don't know where to look and I was hoping for some help. Any suggestion would be much appreciated. Thank you in advance.
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    What are the latest advancements in optics research?

    I have read some articles on invisible cloaks and the creation of a prototype in November from a Greek scientist but I am not really into optics and I don't know what's going on right now in this field.
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    What are the latest advancements in optics research?

    I have taken for this semester an optics course and my teacher will ask us to do a bibliographic research on an optic's subject of our selection. I was interested in finding good topics maybe with a research attention from the modern scientific world. Any ideas?
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    Just a few questions - calculating the average speed and John's speed

    In g, john's speed is the weighted mean of his speed in the different parts of his journey. In h, john's average speed in the whole journey is the total displacement divided by the time of the journey.
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    Right hand rule - Magnetic field

    It's just like any other cross product. AxB Step 1: You put your open palm with your fingers pointing in the same direction as the first vector A ( in your example it is I) Step 2: Without moving anything but your fingers, point to the direction of the point whose magnetic field you examine...
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    Electric field of a disk

    I suppose you talk about a disk ( on your first statement you talk about "ring"). For the ring you have the field of a line so you multiply your linear density with λdx = λrdθ. Now you have a surface with density σ. So dq = σda = σ(2πrdr). Draw a diagram and you will see the validity of that...
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    Electric field point charges

    Why don't you set the distance from the first charge x and define the distance from the other with x and the distance between the two charges? Thus you introduce only one variable in one equation.
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    Electric Field Calculation for Infinitely Long Charged Line and Rod

    The charge of the infinitesimally small part of the rod with length dy is λ(rod)*dy. Which is the force that acts on it? since you have found the electrical field that the line produces, then the force that exerts on a charge which lies in distance s from it is: dF = E(s)*dq.
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    Electrostatics: Equilibrium distance & Acceleration

    (I suppose from your post that when it says the equilibrium distance it refers to the position where B takes no force). You use coulomb's law to find the electric force from A to B. But on B acts gravity too. So you have the gravitational attraction too. The component of gravity on the vertical...
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    Surface Area frictional force

    Surface doesn't affect the friction. If the mass is larger then the frictional force is larger due to the increase of normal force. Especially: Frictional force = μk * normal force *μk depends only by the nature of the surfaces in touch
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    Seemingly easy mechanics problem (constant acceleration)

    Yes when you integrate a = dv/dt = -5 ! you get v = -5t + v0 (=100) not v= -(5/2)t +100. ;)
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    Projectile Motion Questions: Solving for Height, Velocity, and Time

    1. The balloon has constant speed. So where is it 10s before it hits the ground. 2. Right 3. How did you find that if you didn't know how high was it when released? You should better consider it again. (It is also wrong) 4. Nope... The basket continues falling in the same speed as before. The...
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    Seemingly easy mechanics problem (constant acceleration)

    With just calculus you just got wrong the formula of v. You have a= -2.5 . When you integrate that you have? not t^2 obviously...
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    Coulomb's Law and Electric Force

    When it says literal i believe it means an approximation you should make. This approximation is that for small θ, sinθ = θ
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    Electrostatics: Equilibrium distance & Acceleration

    1. Initially C is neutral (Q = 0) so in the first question you don't need to consider C. Generally when you want to determine the equillibrium distance you write down all the forces on the body you study and find the point that their sum is zero. Of course take care of the signs. 2. It is...
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