a)., b)., and c). are completely false.
There isn't a grain of truth among them.
In Physics, the technical definition of 'Work' is (force) times (distance).
Answer:
600m
Explanation:
30×20 at a constant speed is 600m.
NO musical instrument produces a 'pure' tone with only a
single frequency in it.
EVERY instrument produces more or less harmonics (multiples)
in addition to the basic frequency it's playing.
The percussion instruments (drums etc) are the richest producers
of bunches of different frequencies.
Fuzzy electric guitars are next richest.
The strings and brass instruments are moderate producers of
harmonics ... I can't remember which is greater than the other.
Then come the woodwinds ... clarinet, oboe, etc.
The closest to 'pure' tones of single frequency are the sounds
made by the flute and piccolo, but even these are far from 'pure'.
The only way to get a true single-frequency sound is from an
electronic 'sine wave' generator.
Answer is d using a heavier string
A) work = force * distance
mass is not a force, weight is, so we have to find the weight of the block.
Weight = mg
Weight = (220kg)(9.8)
Weight = 2156N
Work = 2156N * 3.10m
work = 6683.6J
b) Since he is holding the weights, it's not moving, therefore, he doesn't do any work
c) The answer is still the same amount of work when he lifted them.
d) The answer is no since when he let go the weight, he doesn't apply any force to the weight.
e) P = work/time
P = 6683.6J / 2.1s
P = 3182.67 watts