# currents

1. ### Find the speed of a copper loop falling in a magnetic field

Hi all, so I had this problem and on the exam and I got a solution but I had an mass-term in there which wasn't given. I used Farraday's Law of Induction to get the Voltage induced. Then I used $rho* \frac{A}{4a}$ for the resistance and divided the Voltage by that to get the current. I then...
2. ### Power loss when fan is connected; finding current

1. Homework Statement An electric fan which is plugged into a 115 V(rms), 60 Hz socket in your house can be considered as made up of a 1500 Ω resistor in series with a 1.4 H inductance. How much power is dissipated by this electric fan on the average? (in W) 2. Homework Equations P = IV = I^2...
3. ### Rudders, sails with holes

I have read articles regarding Chinese junks which utilise rudders made of rubber, and they usually have diamond shaped holes in them. These articles claim that the holes provide better handling of the junks compared to a full rudder without holes in them. What are your thoughts regarding how...