In the Drake equation, Nc = N* × fp × nHZ × fL × fI × fs, the factor nHZ is:
A) the average number of planets in a solar system.
B) the average number of stars that have planets.
C) the average number of planets where life evolved to intelligence.
D) the average number of planets in each solar system suitably placed in the habitable zone.
D
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RC Circuits: A resistor with a resistance of 360 ? is in a series circuit with a capacitor of capacitance 7.3 × 10-6 F. What capacitance must be placed in parallel with the original capacitance to change the capacitive time constant of the combination to three times its original value?
Fill in the blank(s) with the appropriate word(s).
A battery and 5 identical bulbs are arranged as shown. What happens when switch S is closed?
An electron has a kinetic energy of 10 eV. What is the wavelength of this electron?
A) 5.9 × 106 m B) 1.2 × 10-10 m C) 1.9 × 106 m D) 3.9 × 10-10 m E) 3.8 × 10-6 m
Which of the following statements is true?
a. Newton's laws cannot be made to work in accelerated reference systems. b. Newton's laws work in all systems, including accelerated reference systems. c. Newton's laws work in accelerated reference systems if inertial forces are included. d. The fictitious forces cannot be used because they are not real. e. Newton's first law fails in an accelerated reference system, but the second and third laws do not.