In physics lab, you hang a wire perpendicular to the magnetic field created by a horseshoe magnet. You observe that the wire moves downward when you allow
current to flow throligh it. What happens when you reverse the direction of current?

a) The wire moves toward the South pole of the magnet.

b) The wire moves further downward.

c) The wire moves upward.

d) The wire moves toward the North pole of the magnet.

Aplane flies directly between two cities, a and b, which are separated by . from a to b, the plane flies into a headwind. on the return trip from b to a, the wind velocity is unchanged. the trip from b to a takes less than the trip from a to b. what is the airspeed of the plane, assuming it is the same in both directions

Three different objects, all with different masses, are initially at rest at the bottom of a set of steps. each step is of uniform height . the mass of each object is a multiple of the base mass : object 1 has mass 4..00m , object 2 has mass 1..96m , and object 3 has mass . when the objects are at the bottom of the steps, define the total gravitational potential energy of the three-object system to be zero. if the objects are then relocated as shown, what is the new total potential energy of the system? each answer requires the numerical coefficient to an algebraic expression. each algebraic expression is given using some combination of the variables , , and , where is the acceleration due to gravity. enter only the numerical coefficient. (example: if the answer is 1..23mgd , just enter 1.23)

What are similarities and differences of reflection, refraction, diffraction and absorption?