Answer:
Explanation:
The kinetic energy of an object is given by 
where 
is the mass of the object and 
is the velocity of the object.
We can set up the following equations with the information given:
For part B, we have the same equation, but kinetic energy is now 
.
Therefore:
.
Second hand:
1 rev per minute = (2π radians/minute) x (1 min/60sec) = π/30 rad/sec
Minute hand:
1 rev per hour = (2π radians/hour) x (1 hr/3600 sec) = π/1800 rad/sec
Hour hand:
1 rev per 12 hours = (2π rad/12 hr) x (1 hr/3600 sec) = π/21,600 rad/sec
As long as the clock is in good working order, and the hands are turning steadily at their normal rate, there is no angular acceleration.
Answer:
Protecting the Seashore
Seashore Conservation Code
When investigating a seashore it is important to remember that the welfare of the plants and animals must come first. If seaweeds are attached to rocks do not try to pull them off, just examine them where they are growing. Handle animals with great care, returning them to the place where they were found. Anemones and limpets are normally firmly stuck to rocks and any attempt to remove them may result in their death. Replace any large stones that are removed – animals that live on the underside soon die if left exposed.
Pollution Problems
Seas and seashores are under continual threat from pollution. Here are some examples:-
oil rigOil spills, either accidental or deliberate, have a devastating effect on marine life, especially seabirds. Black tar-like oil washed up on a rocky shore would obviously completely destroy the entire community of living things. Chemicals used to disperse oil spills on a shore may effectively clean up the oil, but they can also cleanse the shore of life! The best policy for marine life is to physically remove as much oil as possible and leave the rest to degrade naturally. A rocky shore will recover much more quickly if chemicals are not used.
Sewage and litter also upsets seashore ecosystem, making them unsightly and perhaps contaminated. Some litter can be dangerous to wildlife.
Toxic chemicals and radioactive waste - a cocktail of toxic chemicals have found their way into the sea over the years, affecting both marine and human life. For many years potentially deadly radioactive waste from nuclear power stations and other sources was disposed of in the sea, and beaches have been contaminated by accidental leakages from nuclear power stations.
Explanation:
Answer:
Explanation:
a) Power consumption is 4100 J/min / 60 s/min = 68.3 W(atts)
work done raised the potential energy
b) 75(9.8)(1000) / (3(3600)) = 68.055555... 68.1 W
c) efficiency is 68.1 / 68.3 = 0.99593... or nearly 100%
Not a very likely scenario.
Terminal velocity is when something stops accelerating and just goes at one constant speed so if you put it into a sentence it would be like the rock falling off of the cliff did not accelerate instead it stayed at a terminal velocity
