Which of the following actions would double the magnitude of the magnetic force per unit length between two parallel current-carrying wires? a. Double both currents.
b. Double the distance between them.
c. Reduce the distance between them by half.
d. Double one of the currents.

As a pendulum bob swings back and forth several times, the maximum height it reaches becomes less and less. this is because more and more of the pendulum bob's energy is being transformed into a. heat energy b. kinetic energy c. potential energy d. kinetic energy and potential energy