Answer:
An apple hanging at a branch has potential energy due its position. It can be written as PE= mgh where m is the mass of the apple h is the distance between the apple and the ground and g is the acceleration due to gravity.
as the apple falls from the tree it loses its potential energy and gains kinetic energy due to the movement of the apple. Its kinetic energy will be given by KE= 1/2mv² where m is the mass of the apple and v is the speed with which the apple falls.
As the apple falls the height or the distance reduces and PE becomes reduces. But it gains Kinetic energy due to its speed.
But when the apple falls to the ground and comes to rest its kinetic energy is converted to potential energy.
thus the total energy remains the same. it changes from one form to the other but remains unaltered.
4. 1 and 2 only.
1. the downward force is the force of gravity.
<span>2. The upward force exerted is the Normal reaction from the floor.</span>
Icecaps that are dissolving, a system of canal-like geometric features, and various pitch black surface markings are all thought to be vegetation are the observations of the martian surface led Lowell to the conclusion that intelligent life forms existed on Mars.
<h3>What is a solar system?</h3>
It is a system that collection of all the planets and spatial bodies revolving around the sun because of the gravitational pull of the sun.
Our Solar System is based on a heliocentric model in which the Sun is assumed to reside at the central point of the planetary system.
In other words, the Sun is at the center while the Earth and other planetary bodies revolve around it.
Lowell came to the conclusion that intelligent life existed on Mars based on his observations of the martian surface, which included melting icecaps, a network of geometric patterns that resemble canals, and numerous markings on the completely black surface that are believed to be flora.
Learn more about Solar systems from here,
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I believe the answer would be c because i think that you multiply the 2
