When you move a magnet into a coil of wires, it induces a current in the wires. When you take the same magnet and move it in the opposite direction through the coils, it still induces a current. What is differnet about the currents created in these situations?

True or false: the cycle of seasons on the earth is caused by the tilt of the earth on its axis toward and away from the sun.

Critical mass is the of material required to produce a chain reaction. a.) minimum amount b.) atomic mass c.) precise amount d.) maximum amount

Large electric fields in cell membranes cause ions to move through the cell wall. the field strength in a typical membrane is 1.0 x 10 7 n/c. what is the magnitude of the force on a calcium ion with charge +e? what is its acceleration? is it possible for a particle with the same charge as as calcium to have a different acceleration if placed at this location? what would change the acceleration: mass of the particle? diameter of the particle?