What is the f-number of a camera lens that has an aperture-opening diameter of 0.30 cm and a focal length of 6.0 cm?
a. 0.30
b. 1.8
c. 20
d. 6.0
e. 0.05
c
You might also like to view...
The core of the Sun is
A) at the same temperature and density as the surface. B) at the same temperature but denser than the surface. C) hotter and denser than the surface. D) constantly rising to the surface through convection. E) composed of iron.
A ball is thrown against a wall, bounces off, and is caught. The number of impulses acting on the ball is
1) one. 2) two. 3) three. 4) none. The greatest impulse occurs when the ball 5) is thrown. 6) bounces against the wall. 7) is caught. 8) is zero for each. 9) is nonzero, but the same for each case.
The resolving power of an optical telescope with a diameter of 232 cm is
a. 0.05 arc seconds. b. 232 arc seconds. c. 2.32 arc seconds. d. 5 arc seconds. e. 11.6 arc seconds.
A 1.8-kg block is projected up a rough 10° inclined plane. As the block slides up the incline, its acceleration is 3.8 m/s2 down the incline. What is the magnitude of the force of friction acting on the block?
a. 5.0 N b. 3.8 N c. 4.2 N d. 4.6 N e. 6.5 N