A CD player uses a laser whose light frequency is 3.85 × 10^14 Hz. Calculate the energy, in joules, of the photons
2.55 × 10^–19 J
You might also like to view...
The lowest energy level in an atom is its
a. ionization level. b. emission level. c. absorption level. d. photon level. e. ground state.
Electrons in atoms
a. orbit the nucleus in well-defined circular orbits. b. radiate electromagnetic energy continuously. c. act as if spread out in a "cloud" around the nucleus. d. behave as predicted by quantum mechanics.
A thin spherical copper shell of radius 9.5 cm carries an excess charge of -4.2 nC. How many excess electrons are on
(a) the outer surface of the shell, and (b) the inner surface? (e = 1.60 × 10-19 C)
A 200-? resistor, a 25-mH inductor, and a capacitor are connected in series across an ac voltage source at 1000 Hz. If the impedance of this circuit is 240 ?, which one of the following quantities could be the capacitance of the capacitor?
A) 6.5 ?F B) 4.2 ?F C) 3.2 ?F D) 7.5 ?F E) 5.5 ?F