Which type of wave has a frequency just higher than violet visible light and is used by the skin to produce vitamin d?

a. x-rays

b. microwaves

c. light

d. ultraviolet

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

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?

Which of these metals are magnetic?