Answer:
In a closed system, the total energy is conserved or remains the same as energy transformations take place.
Explanation:
The law of conservation of energy states that energy cannot be created or destroyed but can be transformed from one form to another.
This law of conservation of energy applies only to a closed system. A closed system is a system which does not exchange energy with its surroundings. All forms of energy conversions occurring within a closed system does not result in an increase or decrease of the total energy of the system, rather, energy remains constant. For example, the universe is a closed system in that all forms of energy conversions occurs within it and energy is not exchanged with an external environment. However, the earth is not a closed system as some of the energy it receives from the sun can be radiated out into space. Since it's an open system, its total energy can change.
Answer:
A Magnesia
Explanation:
The word magnetism comes from the word Magnesia, which is the name for a region in Asia Minor, where fragments of Fe3O4 ore (magnetite) were found, which attracts other metal objects.
Magnetism is a physical phenomenon by which we describe the attractive or repulsive force between materials.
This phenomenon has been known for thousands of years.
Answer:
Initial velocity describes how fast an object travels when gravity first applies force on the object. On the other hand, the final velocity is a vector quantity that measures the speed and direction of a moving body after it has reached its maximum acceleration.
Explanation:
working...
Sound wave needs medium to travel
as energy which travels in this wave is because of transfer from one particle to another particle
If there is no medium then energy can not be transferred and sound wave will not travel
so in vacuum we can not listen sound
similarly here air is removed it means there is no medium inside the jar to travel the sound and hence we can not hear it
Option B is correct
Without air, the sound waves cannot travel to the ear.
Answer:
sound Requires a medium in order to travel.
