A radar pulse returns 6.0 × 10-4 s after it was sent out and reflected by an object. What is the separation distance of the radar source and the object?
a. 1.8 × 105 m
b. 9× 104 m
c. 1.1 × 10-3 m
d. 5.6 × 10-4 m
Answer: b. 9× 104 m
You might also like to view...
An 80-km/h airplane caught in a 60-km/h crosswind has a resultant speed of
A) 60 km/h. B) 80 km/h. C) 100 km/h. D) 141 km/h.
A football is thrown upward at some angle above the horizontal. If we neglect air friction, then we can conclude that the acceleration vector of the football is
A. zero. B. down. C. opposite to the velocity vector. D. along the direction of motion.
A 70-kg stunt artist rides in a rocket sled which slides along a flat inclined surface. At an instant when the sled's acceleration has a horizontal component of 6.0 m/s2 and a downward component of 2.8 m/s2, what is the magnitude of the force on the rider by the sled?
a. 0.83 kN b. 0.98 kN c. 0.65 kN d. 0.68 kN e. 0.72 kN
A huge explosion is heard 20 miles away. How long does it take the sound to travel that far? (20 miles = 32,000 meters)