It means that the potential difference between the metal can and the little button on top of the battery is about 1.5 volts.
That's strictly the result of the chemicals in the battery, and has nothing to do with its size. If a battery as big as a house has the same chemistry inside that the AA has, the big one will also have 1.5 volts between its terminals. (But it'll run your flashlight much longer than the AA will, before it runs down.)
(20 seconds / 40 vibes) = (20/40) (seconds/vibe) = 0.5 second
Answer: 62.5 km/hour is the average velocity of the train.
Explanation:
Displacement of the train = 100 km + 150 km = 250 km
Total time train took =1 hour 15 min+ 45 min + 2 hours = 240 min = 4 hours
Average velocity=
62.5 km/hour is the average velocity of the train.