Two short lengths of wire carry currents as shown. (The current is supplied by discharging a capacitor.) The diagram shows the direction of the force on wire 1 due to wire 2.
What is the direction of the force on wire 2 due to wire 1?
Consider a charged capacitor placed in a uniform B field in the +y direction. z points along the capacitor axis, so that x points upward.
Which way does the stored field momentum in this system point?
Now "short out" this capacitor with a small wire. As the current flows, (while the capacitor is discharging)...
which way does the magnetic force push the wire (and thus, the system)?
Feynman’s Paradox: Two charged balls are attached to a horizontal ring that can rotate about a vertical axis without friction. A solenoid with current I is on the axis. Initially, everything is at rest.
The current in the solenoid is turned off. What is the direction of the induced E when viewed from the top?
Feynman’s Paradox: Two charged balls are attached to a horizontal ring that can rotate about a vertical axis without friction. A solenoid with current I is on the axis. Initially, everything is at rest.
The current in the solenoid is turned off. What happens to the charges?
Does the Feynman device violate Conservation of Angular Momentum?
A function, f(x,t), satisfies this PDE:
∂2f∂x2=1c2∂2f∂t2
Invent two different functions f(x,t) that solve this equation. Try to make one of them "boring" and the other "interesting" in some way.
A function, f(x,t), satisfies this PDE:
∂2f∂x2=1c2∂2f∂t2
Which of the following functions work?