A knight on horseback holds a 9.0-m lance. The horse can run at 0.75c. (It wins most of its races!) How long will the lance appear to a person that is standing still on the ground as the horse runs past?
a. 6.0 m
b. 14 m
c. 9 m
d. 6.8 m
e. 4.5 m
a
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When a fixed amount of ideal gas goes through an isothermal expansion
A) its internal (thermal) energy does not change. B) the gas does no work. C) no heat enters or leaves the gas. D) its temperature must decrease. E) its pressure must increase.
A mass of 100 g is attached to one end of a massless rod, 10 cm in length, which is pivoted about the opposite end. The rod is held vertical, with the mass at the top, and released. The rod swings
What is the speed of the mass at the instant that the rod is horizontal? A) 0.71 m/s B) 4.0 m/s C) 2.0 m/s D) 1.4 m/s E) 2.8 m/s
The Earth never passed through the cratering stage in planetary development
Indicate whether the statement is true or false
The nucleus that has the least mass per nucleon is
A) hydrogen. B) iron. C) lead. D) uranium. E) plutonium.