Answer:
Explanation:
Given
mass of crane 
distance moved 
Since it is moving with a constant velocity therefore net force on it is zero
Tension force=weight
T=mg
Work done by Tension T is



Work done by Gravity will be equal in magnitude but opposite in sign and can be obtained by work energy theorem which states that change in kinetic energy of object is equal to work done by all the forces


This would be a physical change because it can change back to its original form. This is like ripping paper. You can piece it back together and it still is paper.
The opposite of this is chemical change. Chemical change means the product has been changed completely like burning paper. The paper has now been turned to ash and it's impossible to change this back to its original form.
Answer and Explanation:
The increasing amounts of greenhouse gases causes climate change and global warming, sea level rises and oceans become warmer.
When prolonged into the future and no actions are being taken; drastic droughts will happen which threatens agricultural in an extreme manner, wildlife living in the forests will be pressurized, and animals/organisms living in the ocean will be affected too due to rising temperature causing the reduced Oxygen effects.
The examples include: the melting of Arctic ice endangering the polar bears, fishes and aquatic marines will die at part of the oceans which has higher temperature (lack of oxygen), poorer regions will have adverse impacts on the human being due to agriculture deterioration and lack of proper system and social readiness to adapt to climate change.
To fight climate change, we must reduce carbon pollution (burning of coals which releases large carbon dioxide/monoxide etc.) through setting up of policies by multinational companies, greener business to reduce emissions, and help people to adapt to climate change or at least educate people about climate change.
Answer:
Explanation:
One of the major differences between nuclear reactions and chemical reactions is that nuclear reactions involve larger amount of energy than chemical energy. <u>This is because the force between the protons and neutrons in the nucleus of an atom is much higher than the force of attraction between electrons and the positively charged nucleus, hence nuclear reactions involves/requires a larger amount of energy (because it's reactions involve the nucleus) than chemical reactions (because it's reactions involve the electrons)</u>.
Thus, during nuclear fusion, two light nuclei are bombarded against one another to produce a larger/heavier nuclei with the release of large amount of energy (because the forces between the protons and neutrons are much higher) unlike when two atoms/molecules are chemically combined together to form a new molecule with the rearrangement of electrons in the valence shells of the participating molecules.