Need !
17. radio waves can bend around buildings. an x-ray technician stands behind a wall during the use of her machine. what does this tell you about the relative wavelengths of these two types of invisible light? use 2 content related sentences. (ref: p.531-539)
23. a positively charged light metal ball is suspended between two oppositely charged metal plates on an insulating thread as shown below. after being charged once, the plates are disconnected from the battery. describe the behavior of the ball. use 3 content related sentences. (ref: p.553-561)
25. three positive charges a, b, and c, and a negative charge d are placed in a line as shown in the diagram. all four charges are of equal magnitude. the distances between a and b, b and c, and c and d are equal. (ref: p.553-561)
a. which charge experiences the greatest net force? which charge experiences the smallest net force?
b. find the ratio of the greatest to the smallest net force.
33. three 15.0-w resistors are connected in parallel across a 30.0-v battery. show all work. (ref: p.624-634)
a) find the current through each branch of the circuit.
b) find the equivalent resistance of the circuit.
c) find the current through the battery.
39. the transmutation of a radioactive uranium isotope, , into a radon isotope, , involves a series of three nuclear reactions. at the end of the first reaction, a thorium isotope, , is formed and at the end of the second reaction, a radium isotope, , is formed. in both reactions, an alpha particle is emitted. write the balanced equations for the three successive nuclear reactions. show all work. (ref: p.808-813)
40. determine the amount of time for polonium-210 to decay to one fourth its original quantity. the half-life of polonium-210 is 138 days. show all work. (ref: p.808-813)