What is the wavelength of the photon emitted when a hydrogen atom which is in the initial state n = 4 transitions to the final state n = 2? (c = 3.00 × 108 m/s, h = 6.626 × 10-34 J ? s, 1 eV = 1.60 × 10-19 J)
A) 243 nm
B) 486 nm
C) 556 nm
D) 312 nm
E) 609 nm
B
You might also like to view...
When the outer envelope of a red giant is ejected, the remaining exposed core of a low mass star is called a
A. black hole. B. white dwarf. C. neutron star. D. red super giant.
A ball tossed vertically upward reaches its highest point and then falls back to its starting point. During this up-and-down motion the acceleration of the ball is always
A) in the direction of motion. B) opposite its velocity. C) directed upward. D) directed downward.
If the frequency of a traveling wave train is increased by a factor of three in a medium where the speed is constant, which of the following is the result?
a. amplitude is one third as big b. amplitude is tripled c. wavelength is one third as big d. wavelength is tripled
An ac circuit has a 20 
F capacitor, an 80 mH inductor, and a 60 
resistor in series. If the voltage source has an angular frequency of 1000 rad/s, what is the phase constant for the circuit?
A. 27
B. 53
C. 45
D. 63
E. 88