Answer:
Minimum work = 5060 J
Explanation:
Given:
Mass of the bucket (m) = 20.0 kg
Initial speed of the bucket (u) = 0 m/s
Final speed of the bucket (v) = 4.0 m/s
Displacement of the bucket (h) = 25.0 m
Let 'W' be the work done by the worker in lifting the bucket.
So, we know from work-energy theorem that, work done by a force is equal to the change in the mechanical energy of the system.
Change in mechanical energy is equal to the sum of change in potential energy and kinetic energy. Therefore,

Therefore, the work done by the worker in lifting the bucket is given as:

Now, plug in the values given and solve for 'W'. This gives,

Therefore, the minimum work that the worker did in lifting the bucket is 5060 J.
55 meters. If she started at 10 meters and ran 45 more, 10+45=55.
Answer:
Tahukah kamu, mengapa motor berhenti di depan lampu merah?
karena motornya direm. Coba kalau nggak direm bisa bahaya tuh.
Tebak binatang apa yang jago renang?
Bebek. Kalau ikan bukan renang tapi menyelam
Kenapa di rel kereta api ditaruh batu?
Soalnya kalau ditaruh duit nanti pada diambil.
Answer: D(t) = 
Explanation: A harmonic motion of a spring can be modeled by a sinusoidal function, which, in general, is of the form:
y =
or y = 
where:
|a| is initil displacement
is period
For a Damped Harmonic Motion, i.e., when the spring doesn't bounce up and down forever, equations for displacement is:
or 
For this question in particular, initial displacement is maximum at 8cm, so it is used the cosine function:
period =
12 =
ω = 
Replacing values:

The equation of displacement, D(t), of a spring with damping factor is
.