At any given moment on Earth, there are about ________ active thunderstorms.
a. 100
b. 200
c. 300
d. 400
Answer: b. 200
You might also like to view...
Silicates
a. are minerals. b. contain silicon and oxygen. c. consist of tetrahedra. d. all of the above.
When it is struck by 240-nm photons, a material having a work function of 2.60 eV emits electrons. What is the maximum kinetic energy of the emitted electrons?
(c = 3.00 × 108 m/s, h = 6.626 × 10-34 J ? s, 1 eV = 1.60 × 10-19 J) A) 2.58 eV B) 5.18 eV C) 2.00 eV D) 4.21 eV
You are serving the volleyball for the second time in a volleyball game. If the ball leaves your hand with twice the velocity it had on your first serve, its horizontal range R (compared to your first serve) would be
A) twice as much. B) half as much. C) times as much. D) four times as much. E) 2 times as much.
If two parallel, conducting plates have equal positive charge, the electric field lines will:
a. leave one plate and go straight to the other plate. b. leave both plates and go to infinity. c. enter both plates from infinity. d. none of the above.