What is the magnitude of a the vertical electric field that will balance the weight of a plastic sphere of mass that has been charged to -3.0 nC? (k = 1/4??0 = 9.0 × 109 N ? m2/C2)
A) 6.9 × 106 N/C
B) 7.8 × 105 N/C
C) 1.5 × 106 N/C
D) 2.1 × 106 N/C
A
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A horizontal desk surface measures 1.3 m by 1.0 m. If the Earth's magnetic field has a magnitude of 0.44 mT and is directed 65
below the horizontal, what is the magnetic flux through the desk surface?
a. 
b. 
c. 
d. 
A 1.56-V battery has an internal resistance of 0.120
What is the maximum current that can be drawn from this battery?
A. infinite (or at least 1000's of amps) B. 1.56 A C. 0.190 A D. 13.0 A E. 7.50 A
Population II stars I. are primarily found in the disk of the galaxy. II. contain more heavy metals than population I stars. III. are primarily old low mass stars. IV. are located in globular clusters
a. III & IV b. I & II c. II d. IV e. I, II, & III
A test rocket is fired straight up from rest with a net acceleration of 20.0 m/s2. After 4.00 seconds the motor turns off, but the rocket continues to coast upward with no appreciable air resistance. What maximum elevation does the rocket reach?
A) 487 m B) 327 m C) 320 m D) 408 m E) 160 m