How can a wire become magnetic? add a resistor

point it north

heat it up

run a current through it

You have been called to testify as an expert witness in a trial involving a head-on collision. car a weighs 1515 lb and was traveling eastward. car b weighs 1125 lb and was traveling westward at 44.0 mph. the cars locked bumpers and slid eastward with their wheels locked for 22.5 ft before stopping. you have measured the coefficient of kinetic friction between the tires and the pavement to be 0.750 . how fast (in miles per hour) was car a traveling just before the collision? (this problem uses english units because they would be used in a u. s. legal proceeding.)

How does the amount of energy required to hold each proton and neutron in the nucleus compare to the energy released when they are removed?

What is the coefficient of kinetic friction μk between the block and the tabletop?