Recent content by Pau Hernandez

Hello, I am confused about the Lorentz Force. For a point charge it is: $$\vec{F} = q \cdot ( \vec{E} + \vec{v} \times \vec{B} )$$ Now from what I understand the E and the B field are external fields. So we are not talking about the fields created by the charge itself. Now where it gets...

One more question Mr. Ibix. Do you know of any good introductory book? Because in my book, it was never mentioned that there is some mechanism that actually has to keep the charge in place. Thats where the confusion about the energy transfer came from.

Oh yes. Thats a good explanation. Funny how the simple things are not so simple after all. Thanks!

Hello people, super confused here. In electrostatics we define the work done on a point charge Q to move it from A to B as $$W = Q \cdot \int_A^B \vec{E} \cdot d\vec{s}$$ . Where exactly does the energy go here? For instance when a positive charge Q is moved in the direction of the electric...

I did. All I found is that the design of the blade has an impact on the power the engine has to output and tension within the blades. Comon design parameters are pitch, size, count. I know that the viscosity of air and water differ. Is that the reason? Thicker, bigger blades to ensure higher...

Why are the blades of air plane propellers thin compared to ship propellers? Why shouldn't air planes use the same blade design?

Hello, I do want to make a small sprinkler for my garden. As you can see it is a simple tube with one end sealed and the other end will be attached to the water hose. Now what I want to do is drill a couple holes to the sides of the tube and get a sprinkler like that. I would like to know how...

The external load is a small door for my dog.

are you referring to my first post or second post?

https://en.wikipedia.org/wiki/Piston_motion_equations well, yes its that simple guys. I am so sorry!

Hello guys, since linear motors are too expensive I decided to buy a rotational motor and use some gears and a crank mechanism to get enough torque and translate rotation into linear motion. I need to meet a certain force on the shaft though. The question is how do I calculate the resulting...

I appreciate the answer, sir. Any resources I can read up on the reversible case?

Hello, according to thermodynamics the compression of a cylinder can both increase pressure and increase temperature. Unfortunately there is no law that gives us boh presure and temperture change given the change of volume, previous temperature and previous pressure? Usually we do either assume...