138 reputation
4
bio website zequez.com
location
age
visits member for 2 years, 2 months
seen Apr 11 at 4:30

Apr
3
comment Why am I getting that work it's always the same in both directions?
Edit: Sorry the $V$ integrals on the first comment should be negative. But the conclusion doesn't really change.
Apr
3
comment Why am I getting that work it's always the same in both directions?
Yes, but the question it's still there, what's that I'm doing wrong with the integrals that I get that $\Delta V_{AB}= \Delta V_{BA}$?
Apr
3
comment Why am I getting that work it's always the same in both directions?
Ok forget about the work. Replace everything with electric potential difference from $A$ to $B$, $\Delta V_{AB} = \int_a^b\vec{E}.\vec{ds}= \int_a^b E.dr.cos(0º)= \int_a^b E.dr$ and then measure the difference from $B$ to $A$, $\Delta V_{BA} = \int_b^a\vec{E}.\vec{ds}=\int_b^a E.dr.cos(180º)= -\int_b^a E.dr = \int_a^b E.dr$, so you get that $\Delta V_{AB} = \Delta V_{BA}$, which is obviously wrong. And of course, if you go by the clearer definition, $\Delta V_{AB}=V_B-V_A$ and $\Delta V_{BA}=V_A-V_B$ it's pretty clear that $\Delta V_{AB} = -\Delta V_{BA}$.
Apr
3
asked Why am I getting that work it's always the same in both directions?
Oct
15
comment I'm having trouble wrapping my head around force, and thus acceleration, diminishing with a higher velocity when using a constant power
But I don't understand why is it relevant that is a rocket. I mean, I could have made the same example with a car, or 2 blocks being pulled with a string.
Oct
15
comment I'm having trouble wrapping my head around force, and thus acceleration, diminishing with a higher velocity when using a constant power
Ok, so, what if it's an electric rocket?
Oct
13
comment I'm having trouble wrapping my head around force, and thus acceleration, diminishing with a higher velocity when using a constant power
But I don't understand, how can an engine use 2 different amounts of power at the same time? How is that physically possible?? I never said acceleration to be constant, I meant the power to be constant, so accelerations diminishes with velocity.
Oct
13
comment I'm having trouble wrapping my head around force, and thus acceleration, diminishing with a higher velocity when using a constant power
Everything but $a_{AB}$, and $v_{AB}$ is relative to an stationary frame of reference. Also, I meant that the power is constant, it stays the same.
Oct
13
asked I'm having trouble wrapping my head around force, and thus acceleration, diminishing with a higher velocity when using a constant power
Feb
27
awarded  Scholar
Feb
27
accepted If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?
Feb
27
comment If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?
The part of the reflection interfering with the rest of the wave was the part that made me understand it (I think). So if this is the case, does it means that the first photons in the wave to reach the "wall" can actually pass through the holes because there wasn't any reflected wave interfering with them?
Feb
27
awarded  Supporter
Feb
27
revised If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?
added 232 characters in body
Feb
27
revised If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?
added 335 characters in body
Feb
27
awarded  Editor
Feb
27
revised If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?
added 420 characters in body
Feb
27
awarded  Student
Feb
27
asked If photons move linearly, what's actually stopping them from passing through a microwave oven mesh?