Sunspot. Sunspots are temporary cooler areas on the Sun's surface caused by changes in its magnetic field.
Solar heating is the system composed of a fluid system to move the heat from the collector to its point of usage and a reservoir to stock the heat
<u>Explanation:</u>
The options given here like coal burning uses solid material as the source to heat and to generate energy. Similarly, nuclear power also requires solid particles like atoms or neutrons to strike the moderators forming energy.
In both of these cases, fluid system is present but it is used completely as coolant and to maintain the temperature. Thus, the remaining system that is solar heating has been done for water tanks where the fluid as water is used to move the heat from its collector to its point of usage. Even in solar system it is used as reservoir to stock the heat.
Explanation:
20 joule is your answer
Answer:
here
mass m =100kg
distance d=50m
acceleration due to gravity a =10m/s²
work =force×displacement
= ma/d=100×10/50=20joule
A. Condensation
Hope this helps!!!
Mass of the displaced material. In water it would be the mass of the water that the volume of the ball displaces.