Which two statements are true of mechanical waves? A. They transfer energy by disturbing electric and magnetic fields.
B. They use a medium to transfer energy.
O c. They travel by causing particles of matter to vibrate.
D. They do not need a medium to transfer energy.

Which wave is the result of amplification and produces a louder sound

What happens when the number of protons in an atom changes

Two 1.20-m nonconducting wires meet at a right angle. one segment carries + 2.50 µc of charge distributed uniformly along its length, and the other carries - 2.50 µc distributed uniformly along it, as shown in fig. 21.50. ( a. find the magnitude and direction of the electric field these wires produce at point p, which is 60.0 cm from each wire. ( b. if an electron is released at p, what are the magnitude and direction of the net force that these wires exert on it?