Recent content by Amr Elsayed

Oh and another thing... the college that I want to attend offers only BA (Hamilton college) while the other (Lafayette college) offers BS People on college confidential told me it doesn't matter at all.

It would also be great if i can get masters in engineering just in case... but I read that employers always choose the applicants who studies engineering in bachelors. I also read that this way I won't obtain something that engineers do obtain and that helps find jobs.

@Dr.D yes, I believe that I'm not very qualified to make this decision right now, but the thing is that I have to. So, to be more specific, what I enjoy about mechanics problems at school is that I get to imagine and relate to the situation being discussed. I love to feel the situation, but...

I'm an international student and I'm going to attend a U.S. college this fall, and in order to decide which college I should pick, I have to make my decision whether or not I would like to major in engineering because the college that I want to attend doesn't have engineering, while the other...

Great, I understand the math. I get that the mathematics implies behaving that way, but I still need a non-mathematical explanation of what happens. Something like: current suddenly increases causing a sudden increase in back emf, then ... and ... which causes them to behave that way.

Indeed I understand how they're related, but my question was why there is an exponential increase in one of them ( current or back emf) so that it affects the other as well. I want to have the sense why does the current need to increase exponentially and the back emf needs to decrease...

Thank you, I could understand what he meant, but I'm not so much concerned with what's happening at t=0 as I am concerned with what's happening later on. I got lost when he integrated the equation he got. I don't know much about integration BTW. So, is it current that is exponentially increasing...

Good evening everyone. I have a misconception regarding self inductance. I know that back emf induced in an inductor starts with the same value of the original voltage source and then keeps decreasing to reach zero. I also know how this is related to the derivative of current with respect to...

Oh.. so it's g that changes to match the change in the weight when an elevator accelerates, and I don't need to be concerned with the inertial mass in classical mechanics. okay, thanks

Is the change in weight due to being in a non inertial frame adjusted with a change in g to keep the m constant or what ?

Actually it's not, but it depends on the inertial mass, right ? if the elevator accelerates the inertial mass would increase or decrease.. but in case the mass we're concerned with is the invariant mass, no change will occur

Yes, I got it... I had some mathematical little problem that I could solve, I now have the intuition how it works. Would you please help me with this ? does instantaneous conversion from an inertial frame to a non-inertial frame like an accelerating elevator have something to do with the period...

Actually I don't want to have the intuition how it's derived. I want to have the intuition how it works. Specifically, I want to know how the equation and the negative sign in it relate to the fact that velocity can be either in the same or opposite direction of the displacement. How can all the...

would you please explain more how 2*pi*f*t could give values ranging from 0 to 180 or to pi and so on... what about the third part ?? how acceleration due to gravity relates to the period of a vertical spring ?? isn't it supposed to merely change the equilibrium position ?

I'm talking about the formula: v= -A* omega * sin( 2*pi*f*t) where did this negative sign come from ? and for what values is x positive and for what values is it negative ? for the third part, i don't get how changing g relates to the period. I know that the period equals 2*pi / omega