Energy Density: A 2.4 × 1014 Hz laser emits a 3.5-?s pulse that is 5.0 mm in diameter. The average energy density in the beam is 0.65 J/m3. What average power is emitted by this laser? (c = 3.0 × 108 m/s, ?0 = 4? × 10-7 T ? m/A, ?0 = 8.85 × 10-12 C2/N ? m2)
A. 3.8 kW
B. 7.7 kW
C. 12 kW
D. 15 kW
E. 19 kW
Answer: A
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Fluid Flow: An ideal incompressible fluid flows at 0.252 m/s through a 44-mm diameter cylindrical pipe. The pipe widens to a square cross sectional area that is 5.5 cm on a side. Assume steady flow throughout the system.(a) What is the speed of the fluid through the square section of pipe?(b) What is the flow rate in liters per minute?
What will be an ideal response?
Impedance: If a 1.0-k? resistor is connected in series with a 20-mH inductor, what is the impedance at 1.0 kHz?
A. 0.13 k? B. 1.0 k? C. 1.1 k? D. 0.13 M?
The existence of the Ring of Fire is best explained by the
a. theory of plate tectonics. b. principle of superposition. c. concept of uniformitarianism. d. law of catastrophism.
Find the binding energy per nucleon (in MeV/nucleon) of carbon-12. Assume: mC = 12.000 000 u m p = 1.007 825 u m n = 1.008 665 u u = 1.66 × 10^-27 kg
a. 1.2 b. 4.2 × 10^-2 c. 7.4 d. 7.7 e. 5.6