Recent content by SecretSnow

Hi everyone, I'm currently looking for a book on ways to sketch curves, especially for the more unusual kinds of curves, something that teaches things like hyperbolic curves, x^x, sigmoid functions and so on. These are what I have not encountered in my learning very often, so I'm interested to...

Hi guys, i need some help here... 1. I know that by convention, the positive charge of the voltage source is taken to be the direction of current, but I'm confused by this MIT lecture vid that drew the current as appearing to be flowing from the negative terminal. You can see the drawing in...

hmm..but why would the situations be different? Why would the work done, because of superposition, be more than original? What's so special about superposition?

Hi guys, let's say we have a wave where the power P is proportionate to the square of its amplitude, which is A^2. If now we have 2 identical waves in superposition in phase, then we have an amplitude of 2A am i right? Next, we realize that because of the amplitude of the superposed waves is...

Hi guys, first off, thanks for answering my previous question... Now here's another one. I got confused by my school's homework a bit...so there's a car that travels over a humpback bridge with a radius of 45m, so basically it's a semicircle bridge, and so I'm supposed to calculate the...

Hi guys, I understand that g is by definition positive, as in the Gravitational field strength. However, my school's notes has defined g as -(GM)/r^2. I don't understand what's that negative sign for, and in what scenario is the negative sign used? By the way, it also defined g as -(d phi/dr)...

Hi guys, this is so confusing as there are lots of assumption needed (I think). I can't do this even though I got the answer and tried working backwards. A painter in a crate which hangs alongside a building, weighs 1000N.When the painter pulls on the rope, the force he exerts on the floor of...

I'm thinking if it could be the work function of anode it's saying, and that there might be electrons of the anode absorbing the photon produced by the colliding electrons? Is this possible? But if the energy of the photon emitted is high enough, then it should be able to liberate the electrons...

Actually I don't get why the textbook even mentions work function in the first place. if the electron is boiled off,then initially if should have low or zero KE, which means by the time it reaches the anode, it should have E=eV. The thing is, does the work function applies in the anode? If yes...

Hi guys, if an electron emitted by the photoelectric effect has E=hf-phi=KE of the electron=eV where V is the stopping potential, what will happen to the electron when a reverse potential (stopping potential) is being used? I'm guessing initially, the KE of the electron is of a positive value...

Hi guys, I'm constantly bothered by one assumption in my textbook..it says that the photon emitted by the accelerating electron boiled off from the cathode colliding into the anode, has E=hf neglecting the work function, since its negligible. I'm curious whether it's E=hf plus or minus the work...

Thanks guys! I think I have an idea of how it works but I'm not sure if it's correct. Initially, if the car is traveling straight, the friction is directly opposite to the direction of motion of the wheel but in the direction of the car, forward (which means when the wheels are rolling forward...

Hi guys, I'm confused why friction is able to cause centripetal acceleration on a car that is turning in a circular road. Firstly, I think the radial acceleration is provided by the engine alone, and at any point of time the car velocity is tangential to the circular path, and friction is only...

Hi guys, basically i have a few questions with regards to Prof Walter Lewin's videos. Firstly, this is the video of him explaining the flywheel concept with energy involved: My question is, why does a flywheel actually spin when the car goes downwards? how does the flywheel actually converts...

Oh wait I noticed my error. The mvr=Iw applies to only to body's angular momentum when rotating by itself and r is the distance to cm from point.