The rms Electric field strength at a distance r from a 25 W light source is found to be 4.33 N/C. What is the distance r?

A. 22 m
B. 6.3 m
C. 30 m
D. 40 m


B. 6.3 m

Physics & Space Science

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Orbital Angular Momentum: What is the minimum angle between the z-axis (or any other axis you choose) and the orbital angular momentum of an electron in the n = 4 state?

A. 30.0° B. 41.4° C. 60.0° D. 45.0°

Physics & Space Science

A person throws three rocks off a cliff of height h at exactly the same speed , each time, but throwing rock A almost vertically upward, rock B horizontally, and rock C almost vertically downward (see the diagram below).

Which rock hits the ground with the greatest speed? (Ignore air friction.) A. Rock A B. Rock B C. Rock C D. Rocks A and C hit with the same speed, faster than B. E. All three rocks hit with the same speed.

Physics & Space Science

Neutron stars are supported by _____

a. hydrogen degeneracy pressure
b. neutron degeneracy pressure
c. neutron gas pressure
d. electron degeneracy pressure
e. hydrogen gas pressure

Physics & Space Science

Which of the following statements is true about the spin-orbit coupling effects on the transitions of an atom such as sodium? Assume sodium is modeled by a single electron atom

a.The difference in the energy of a split state does not depend on the electron's angular momentum, but instead the angular momentum of the nucleus. b. The differences in energy level transitions are significant enough to change the order of filling of the subshells. c.Electrons with a state of l = 0 never have split energy levels. d. For single electron atoms (or atoms with one electron outside a filled shell) each nl state is made a doublet.

Physics & Space Science