Light having a wavelength of 450 nm (4.50 × 10-7 m) moves through space at 3.0 × 108 m/s. What is the frequency of the light? A.1.35 × 102 Hz
B.7.41 × 10-3 Hz
C.1.50 × 10-15 Hz
D.6.67 × 1014 Hz

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?