Consider gliders that slide friction-free along a horizontal air track. Glider A has a mass of 1 kg, a speed of 1 m/s, and collides with glider B, which has a mass of 5 kg and is at rest. If they stick upon collision the combined-glider speed will be
A) 1/4 m/s.
B) 1/5 m/s.
C) 1/6 m/s.
D) 1 m/s.
E) none of the above
Question 2
In the case of light waves, the thing doing the waving is
A) charged particles throughout the region between source and receiver.
B) a gravitational field.
C) the ether.
D) an electromagnetic field.
E) the air.