E) to the side of the flatcar
5. A boy wishes to row across a river in the shortest possible time. He can row at 2 m/s
in still water and the river is flowing at 1 m/s. At what angle 0 should he point the
bow (front) of his boat?
30°
45°
60°
63°
90°
1 m/s
?
6. A boat is able to move through still water at 20 m/s. It makes a round trip to a town
3.0 km upstream. If the river flows at 5m/s, the time required for this round trip is:
A) 120 s
B) 150 s
200 s
D) 300 s
E) 320 s
7. A consequence of Einstein's theory of relativity is:
A) moving clocks run more slowly than when they are at rest
B) moving rods are longer than when they are at rest
C) light has both wave and particle properties
) the laws of physics must appear the same to all observers moving with uniform
(constant) velocity relative to each other
E) everything is relative
8. A meter stick moves in the direction of its length through a laboratory. According to
measurements taken in the laboratory, its length is 0.31m The speed of the meter stick
relative to the laboratory is:
A) 0.096c
B) 0.31c
C) 0.69c
D) 0.83c
E) 0.95c
