a. A dam is usually built at the site of hydroelectric power. As water accumulates, its potential power for producing electric power increases. As this water moves downstream from the dam, mostly through a fall, its kinetic energy is harnessed by turbines and converted to electric energy.
b. One factor is the height of the fall of the water from the dam. The higher the height the higher the kinetic energy of the water and hence can be converted to higher electric energy. The higher the number of coils of the turbine generator being rotated by the water, the higher the conversion to electric current.
c. One is impoundment. This type is the most common and involves the building of a dam to store water and later the water is released to turn turbines. The second type is diversion. This type does not require a dam. Some water is diverted from the main river to create a pen-stock that runs a turbine.
d. The advantage of hydroelectric power is that is is a clean energy source hence does not cause global warming. Global warming can have economic consequences. The operating cost of this type of plant is low hence the costs of electricity are able to be kept low for the consumers. 2 disadvantage is that creating a dam upstream causes a change in the physical and chemical characteristics of the river or water bodies affecting ecosystems. Another is that electricity is dependent on the water regime hence dependency is tied to climate.
Answer:
Number of days needed = 57
Explanation:
Depth of well = 115 feet
Distance traveled in day = 3 feet up
Distance traveled in night = 1 feet down.
Total displacement in 1 day = 3 - 1 = 2 feet up
When the snail reaches 112 feet up, the next 3 feet up motion on day will make it reach the top.

After 56 days the displacement of snail is 112 feet.
On the next day it moves up by 3 feet and reaches out of well.
Number of days needed = 57
Based on the calculations, the speed required for this satellite to stay in orbit is equal to 1.8 × 10³ m/s.
<u>Given the following data:</u>
- Gravitational constant = 6.67 × 10⁻¹¹ m/kg²
- Mass of Moon = 7.36 × 10²² kg
- Distance, r = 4.2 × 10⁶ m.
<h3>How to determine the speed of this satellite?</h3>
In order to determine the speed of this satellite to stay in orbit, the centripetal force acting on it must be sufficient to change its direction.
This ultimately implies that, the centripetal force must be equal to the gravitational force as shown below:
Fc = Fg
mv²/r = GmM/r²
<u>Where:</u>
- m is the mass of the satellite.
Making v the subject of formula, we have;
v = √(GM/r)
Substituting the given parameters into the formula, we have;
v = √(6.67 × 10⁻¹¹ × 7.36 × 10²²/4.2 × 10⁶)
v = √(1,168,838.095)
v = 1,081.13 m/s.
Speed, v = 1.8 × 10³ m/s.
Read more on speed here: brainly.com/question/20162935
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Answer:
Final temperature, 
Explanation:
Given that,
Mass of silver ring, m = 4 g
Initial temperature, 
Heat released, Q = -18 J (as heat is released)
Specific heat capacity of silver, 
To find,
Final temperature
Solution,
The expression for the specific heat is given by :





So, the final temperature of silver is 21.85 degrees Celsius.