Search results

  1. L

    Voltage across two different circuits

    So if I'm understanding correctly, does this mean that according to Ohm's Law, the amount current flowing in a circuit will always change to a quantity that coincides with the potential dropping to zero after the last resistor in the circuit?
  2. L

    Voltage across two different circuits

    I guess what I'm not understanding about this analogy and my big question in general is why the voltage drops all the way to zero after the last resistor. So let's just use your water analogy. The voltage starts out in a pipe and travels through a resistor (pipe with smaller radius), so...
  3. L

    Voltage across two different circuits

    I have a question regarding the voltage of two different circuits. In the first circuit there is a 75 volt battery with just one 4 ohm resistor. In a separate second circuit there is a 75 volt battery again, but this time there is a 4 ohm resistor and 9 ohm resistor in series. My question is...
  4. L

    Irrelevance of electrical potential

    Can you explain what you mean by "add a constant to it." Maybe an example would help me understand what you're saying. Thanks.
  5. L

    Irrelevance of electrical potential

    Thank you for the answer, I think I understand. So would I be correct to say that if the electrical potential at a certain point was 200 J/C, then that means that it would take 200 J of energy to move a 1 C charge from infinity to that point? But in terms of a circuit, the electrical potential...
  6. L

    Irrelevance of electrical potential

    In regards to voltage and electrical potential, I have a question. I understand the voltage to be the difference in electrical potential of two separate points. So in an analogy am I correct to compare this to a bowling ball being 4 feet off the ground. So the bowling ball has a gravitational...
  7. L

    Please Explain Voltage

    Thanks Sheldon, I freaking love you!
  8. L

    What is the voltage at the end of the circuit?

    1. 15 V is what I think 2. 0 V is what I think. And this definitely isn't homework. I'll pulled a pic off google images and made these questions. I could care less about the value if the answer, I want to know the reasoning behind it. Is 1 and 2 correct and why?
  9. L

    Rise in Voltage across a battery

    Let's say you have a circuit connected to a 15 volt battery. If current travels from the negative terminal of a 15 volt battery to the positive terminal, the voltage is said to rise 15 volts. I believe this is right, but correct me if I'm wrong. Assuming that is right, then does that mean that...
  10. L

    Please Explain Voltage

    Thank you so much, and what would be the equivalent of resistors in series? What would be a capacitor in this analogy?
  11. L

    What is the voltage at the end of the circuit?

    I have a some questions that will help me understand voltage better. 1. What is the voltage from the positive terminal to the negative terminal? Why? 2. What is the voltage from point 7 to point 8? Why? 3. Is the electric potential at the very end of the circuit (negative terminal) zero...
  12. L

    Please Explain Voltage

    Homework Statement I am trying very hard to understand voltage. I am a second year engineering student in a physics II class. I am having trouble grasping the concept of voltage. Could you guys please help me out with a few questions. Please correct me if I am wrong, but isn't voltage the...
  13. L

    What is the electric field at this point?

    Homework Statement A charge -3.2 micro-coulombs is spread evenly throughout a rod of length (a). At a distance (b) from the rod, what is the electric field? a = 1.2 m b = 3.4 m So basically, you start at zero and then there's a line of charge horizontally to the right from 0 to 1.2 meters...
  14. L

    What is the charge density on the insulator?

    Homework Statement Insulator has a 3 cm radius and is a sphere. It has a total charge of -4.2 uC. I need to find the charge density of the insulator. Homework Equations sigma = total charge / volume.... I think? The Attempt at a Solution After using the above equation, I got -3.714E-8 C/m...
  15. L

    Electrostatic Force

    Thank you, that's makes a lot of sense. After reading a little bit, I understand newton's third law in an intuitive sense now.
  16. L

    Electrostatic Force

    Homework Statement I have a question that I think I know, but it is kind of confusing me a little bit. The problem is as following: Consider a charge of +3.2 C and a charge of -1.6 C separated by a distance of radius r. Which of the following statements correctly describes the magnitude of...
  17. L

    How is tension in a string affected by moment of inertia?

    Wow, that was actually really easy to understand. Thanks for the simple straightforward explanation, you're the GOAT.
  18. L

    How is tension in a string affected by moment of inertia?

    Homework Statement I'm in need of a more conceptual answer, rather than numerical. Say you have a block on a horizontal frictionless table (block 1). Then you have a string tied to block one and strung over a pulley that is at the right end of the table (the pulley has mass). On the other...
  19. L

    What is the minimum mass of the barbell without tipping?

    Never mind, I got the answer myself haha.
  20. L

    What is the minimum mass of the barbell without tipping?

    I'll try to find the page I did this on, but the mass of the bar is what I'm trying to find.
  21. L

    What is the minimum mass of the barbell without tipping?

    Homework Statement Typical weight sets used for bodybuilding consist of disk-shaped weights with holes in the center that can slide onto 2.20 m long barbells. A barbell is supported by racks located a fifth of its length from each end, as shown in the figure. What is the minimum mass m of the...
  22. L

    Why does I*a = TR?

    Okay wow that makes a lot more sense. I didn't know that was the exact definition. I thought it was just some sort of angular force. Makes a lot more sense now, I understand. Thanks a lot!
  23. L

    Why does I*a = TR?

    I understand that T = Ia is the rotational analog of F = ma, but why does the tension * radius = Ia? Why does TR = Ia... why are both Ia and TR both equal to torque?
  24. L

    Why does I*a = TR?

    Homework Statement I am first learning about angular motion and came across this formula while doing a homework problem. Can anyone explain to me why ɪa = TR? That is the moment of inertia * angular acceleration = tension in rope * radius. For reference, in the problem it's a stunt guy jumping...
  25. L

    Recoil velocity of a cannon

    Nvm guys. I got the answer easily after I figured out it had nothing to do with center of mass, and when I figured out what recoil velocity was. I thought it was asking for how fast the barrel of the gun would fly back, but it was talking about how fast the whole tank would move backwards... easy.
  26. L

    Recoil velocity of a cannon

    Homework Statement A 1000 kg cannon shoots a 30 kg shell at an angle of 25 degrees above the horizontal and a speed of 500 m/s with respect to the ground. What is the recoil velocity of the cannon? Homework Equations Not sure The Attempt at a Solution I really don't know where to begin. The...
Top