Moving a ball up a hill O A. increases its chemical energy
OB. decreases its chemical energy
O C. increases its potential energy
OD. decreases its potential energy

1-10. need . physics. circular motion. 35 points

Which of the following statements are true of solids? a.the particles do not vibrate. b.the particles are in a fixed location. c.they have strong intermolecular forces between the atoms or molecules. d.the particles have less kinetic energy than those of liquids or gases.

What is the function of the commutator in a dc motor? a. to spin the magnet b. to change direct current into alternating current c. to change alternating current into direct current d. to spin the wire coil