Reducing the magnetic field to 71% of its previous value changes the magnetic energy density in the field to _______% of its original value.
A. 39
B. 50
C. 71
D. 85
E. 15
B. 50
You might also like to view...
Why are millisecond pulsars often found in binary systems with small red- or brown-dwarf companions?
What will be an ideal response?
Intensity: An 8.00-mW laser beam emits a cylindrical beam of single-wavelength sinusoidal light 0.600 mm in diameter. What is the maximum value of the magnetic field in the laser beam? (?0 = 8.85 × 10-12 C2/N ? m2, ?0 = 4? × 10-7 T ? m/A, c = 3.0 × 108 m/s)
A. 9.24 µT B. 17.2 µT C. 12.4 µT D. 20.5 µT E. 15.4 µT
The strength of gravity within a molecular cloud depends on
A) density only. B) temperature only. C) density and temperature. D) composition. E) thermal pressure.
A howler monkey is the loudest land animal and, under some circumstances, can be heard up to a distance of 5.0 km. Assume the acoustic output of a howler to be uniform in all directions and that the threshold of hearing is 1.0 × 10-12 W/m2
The acoustic power emitted by the howler is closest to A) 0.31 mW. B) 0.11 mW. C) 1.1 mW. D) 3.2 mW. E) 11 mW.