The focal length of a camera lens is 40 mm and its aperture diameter is 10 mm. What is the f-number of this lens?
A) 0.40 B) 5.6 C) 2.0 D) 4.0 E) 0.25
D
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The majority of galaxies in the local group are irregulars and small ellipticals. This fact proves that the majority of galaxies in the Universe are of the irregular or small elliptical type.
Answer the following statement true (T) or false (F)
An electron, initially moving at 2.0 × 104 m/s along the +x-axis, experiences a constant acceleration of 1010 m/s2 in the +y direction. How far from its starting point is the electron after 4.0 × 10-6 seconds?
A) 8.0 m B) 11.3 m C) 9.8 m D) 11.3 cm E) 8.0 cm
The condensation sequence cannot explain the composition of the terrestrial and Jovian planets
a. True b. False Indicate whether the statement is true or false
Consider the following statement, and explain whether or not it is sensible: Someday we may build spaceships capable of traveling at a speed of 1 light-second per hour
What will be an ideal response?