Answer:
Red giant or super giant → very cool but very luminous
→ found in the upper right of the H-R diagram.
Main sequence →The majority of stars in our galaxy
→ Sun, for example
→ a very hot and very luminous star
White dwarfs → very hot but very dim
→ not much larger in radius than earth
Explanation:
Giant:
When the stars run out of their fuel that is hydrogen for the nuclear fusion reactions then they convert into Giant stars.That's why they are very cool. Giant stars have the larger radius and luminosity then the main sequence stars.
Main Sequence:
Stars are called main sequence stars when their core temperature reaches up to 10 million kelvin and their start the nuclear fusion reactions of hydrogen into helium in the core of the star. That is why they are very hot and luminous. For example sun is known as to be in the stage of main sequence as the nuclear fusion reactions are happening in its core.
White dwarfs:
When the stars run out of their fuel then they shed the outer layer planetary nebula, the remaining core part that left behind is called as white dwarf. It's the most dense part as the most of the mass is concentrated in this part.
Answer:
Explanation:
In physics, a conservation law states that a particular measurable property of an isolated physical system does not change as the system evolves over time. The exact conservation laws include conservation of energy, and conservation of linear momentum, and also conservation of angular momentum, aswell as the conservation of electric charge
Option (a) is correct.
Falling objects accelerate as they approach the ground.This is because of the force of gravity acting on the falling objects. so the velocity of these objects increases continuously as they approach the ground. the acceleration acting on the falling objects is a constant ( close to the surface of earth) and is called as acceleration due to gravity denoted by g. value of g=9.8 m/s².
Answer:
When the parachute opens, the air resistance increases. The skydiver slows down until a new, lower terminal velocity is reached.
