Recent content by aviv87

My school is conducting a special day, for teenagers in junior high that are considering signing up to my school. During this day students can do all sorts of experiments to interest the teenagers to study them. I am searching for simple yet interesting experiments in physics. Can anyone...

Well, if they have a total inelastic collision then after the collision they move together, as one body, with the same velocity, right? So all you've got to do is use the momentum conservation law to compare the total momentum before the collision and after it and then find the velocity...

Hmm.. 1. We choose one of the spheres. You decide to mark its location as the origin. This means we have 1 sphere on the x-axis .6 m from it, another on the y-axis, and a third one right between them, .6*sqrt(2) m from it. Use the formula F=G\frac{M_{1}M_{2}}{r^{2}} and calculate the sum of...

Also, if you know how to calculate potential gravitational energy and kinetic energy you could use the energy conservation law.

Actually, considering the options he was given, I'd say in his course the acceleration due to gravity is used as 10\ m/s^2

And what about the gravitational force between the two electrons? Shouldn't it be considered?

Thank you both very much! I got it now =)

First of all thanks for answering =) I understood that one of the resistors in A's nearest triangle and in B's doesn't affect the total resistance, but I don't understand why the resistance of the other triangle is (2/3)R. Can you please explain to me how you got that? o:)

Hey, I am trying to calculate the total resistance for this but I always come up with the wrong answer. A picture is available http://img109.exs.cx/img109/5889/physics.jpg In this picture every blue line is supposed to be a resistor with resistance R (yeah, I know it's ugly :-p ) The...

Well, about the second question, if the sailor lands the boat at X km down the point directly opposite her then she has rowed \sqrt{8^{2} + x^{2}} km and she needs to run another (10-x) km. Using this calculate how much time she spends passing each part and then do the derivation.

Well, there's no system. At each level you just take each letter from the word you want to "get to" and see if it fits the word you've got. Note that the order of the letters in each step isn't scrambled. For example, in the first one the only letter that can be placed in its place from...

Well, you know that T = 30/8 = 3.75 And T=2\cdot\pi\cdot\sqrt{\frac{m}{k}} => k = 561.47[N/m] You also know that 20m under the bridge a=0 \Sigma \vec{F} = 0 mg=k\Delta L Now you just need to get \Delta L. HTH

My thoughts exactly :approve: Well, I guess he wasn't paying enough attention or something... Thanks!

Well, that's what I got, but my physics teacher said he thinks it's a=0 for the bottom one, but that the one on top would have a<g, but he wasn't sure. That made me think I did something wrong...

there's a spring connected to a ceiling. a mass M is connected to it, to her another spring is connected, another mass etc' for N masses. ceiling ----- / \ / M \ / \ M \ / \ M Does this help? :smile: