Refracting Telescope: A refracting telescope has a magnification M. If the focal length of the objective lens is doubled and the eyepiece focal length is halved, what is the new magnification?
A. 4M
B. 2M
C. M/2
D. M/4
E. M
Answer: A
You might also like to view...
Repeat Problem 9.23 for a tier of six horizontal 2.5-cm-OD tubes under similar thermal conditions.
GIVEN
? Saturated steam condensing on horizontal tubes
? Tube outside diameter (D) = 2.5 cm = 0.025 m
? Tube outer surface temperature (Ts) = 27°C
? Steam pressure (p) = 12 kPa
? Number of tubes (n) = 6
FIND
? The average heat transfer coefficient (hc)
ASSUMPTIONS
? Steady state
? Film condensation occurs
SKETCH
PROPERTIES AND CONSTANTS
From Appendix 2, Table 13, for saturated water at 12 kPa
The temperature of the Sun's core is about 20,000 K
Indicate whether the statement is true or false
Why is it difficult to directly measure the size of a star's disk from Earth?
What will be an ideal response?
A square, flat loop of wire is pulled at constant velocity through a region of uniform magnetic field directed perpendicular to the plane of the loop as shown in Figure OQ31.5. Does charge separation occur in the coil?