Which of these variable stars would be classified as an RR Lyrae?
A) a pulsar with a period of 0.14 seconds
B) a K giant with a period of 14 days
C) an M giant with a period of 140 days
D) an F giant with a period of 14 hours
E) a B supergiant with a period of 0.14 days
D
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A cantilever beam with rectangular cross section (b 5 95 mm, h 5 300 mm) supports load P 5 160 kN at its free end. The ratio of the magnitudes of the principal stresses (?1/?2) at point A (at distance c 5 0.8 m from the free end and distance d 5 200 mm up from the bottom) is approximately:
(A) 5
(B) 12
(C) 18
(D) 25
Suppose two lines appear to be parallel but eventually meet. What type of geometry are you dealing with?
A) flat geometry B) spherical geometry C) saddle-shaped geometry D) Euclidean geometry E) This situation can never occur.
How fast does light travel from Proxima Centuri to Earth?
a. 4.2 ly b. 4.2 years c. 3 × 10^8 m/s d. None of the other choices are correct.
The small piston of a hydraulic lift has a diameter of 8.0 cm, and its large piston has a diameter of 40 cm. The lift raises a load of 15,000 N. Assume the pistons each have negligible mass
(a) Determine the force that must be exerted by the fluid in the lift on the small piston. (b) Determine the pressure applied to the fluid in the lift.