What does an electromagnet have that a bar magnet does not ?

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

The transfer of heat through the movement of a gas or liquid a. convection b. conduction c. radiation

Along wire carrying a 4.2 a current perpendicular to the xy-plane intersects the x-axis at x=−1.7cm. a second, parallel wire carrying a 3.0 a current intersects the x-axis at x=+1.7cm. part a at what point on the x-axis is the magnetic field zero if the two currents are in the same direction? express your answer to two significant figures and include the appropriate units.