# Search results

1. ### 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...
2. ### 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...
3. ### 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...
4. ### 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...

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...
6. ### 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...
7. ### 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...
8. ### 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...
9. ### 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...
10. ### 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...
11. ### 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...
12. ### 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...