A book rests on a level table top. Which force does Newton's third law imply is equal in magnitude but opposite in direction to the weight of the book?
A)
the force of the table on the earth
B)
the force of the earth on the table
C)
the force of the book on the earth
D)
the force of the table on the book
E)
the force of the book on the table
Question 2
A plane electromagnetic wave propagates in a vacuum in the z-direction. The wave has a wavelength of 10 m and the electric field is along the +x direction and has an amplitude of is 0.20 V/m, with one maximum at x = 0 and t = 0.
What is the mathematical expression for the magnetic field? A)
By = 0.067 10-8sin(0.63 m-1)z - (2.1 10-9 s-1)t T
B)
By = 0.067 10-8sin(0.63 m-1)z + (2.1 10-9 s-1)t T
C)
By = 0.067 10-8cos(0.63 m-1)z + (1.9 108 s-1)t T
D)
By = 0.067 10-8cos(10 m-1)z - (2.1 10-9 s-1)t T
E)
By = 0.067 10-8cos(0.63 m-1)z - (1.9 10-8 s-1)t T