The formation of a standing wave requires

constructive interference between two waves with different frequencies

interference between the incoming and reflected waves of the same frequency

two waves that have been traveling over a long distance

The plum pudding model of the atom state that ?

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?

Observations show that interstellar clouds can have almost any shape and