<span>According
to the special theory of relativity, all laws of nature
are the same in
reference frames that move at constant speeds.
That means that there's no test or measurement you can do to
detect whether you're moving at a constant speed</span> or how fast.
And THAT means that there's no such thing as "who's REALLY
moving" and "who's REALLY at rest". There's no such thing as
"real" motion, only motion relative to something else.
Answer: Water fills the bucket until its force/weight is greater than the block’s. The lever tilts over, causing the bucket to water the plant.
The 1/2 value comes due to the integration of the Newton's law of motion .. like for doing work we do integrate fds vector. when we integrate it .we get it as 1/2mv^2 + constant
.