Answer the following question given this paragraph: Energy is a measure of the amount of or potential for movement in something. The total amount of energy in the universe is always the same. This symmetry is called a conservation law. Conservation of energy is one of five conservation laws that govern our universe. A group of things (we'll use the word system ) has a certain amount of energy. Energy can be added to a system; for instance, when chemical bonds in a burning log break, they release heat. Energy can be lost from a system; for instance, when a spacecraft "burns up" its energy of motion during re-entry, it loses energy and the surrounding atmosphere gains the lost energy. A closed system is one for which the total energy does not change, or is conserved . In this chapter, we will often consider closed systems, for which the total amount of energy stays the same, but transforms from one kind to another. The transfer of energy from one system to another is called Work . Work is equal to the amount of energy transferred in (positive work) or out (negative work) of a system. Work is equal to the distance the object is moved multiplied by the amount of force in the direction of its motion. The rate at which work is done is called Power . Q: What happens when chemical bonds in a burning log break? Choices: - remove heat - hold heat - decrease heat - release heat A:
release heat
(Question)
Answer the following question given this paragraph: The Figure below shows the direction of the current that is generated by a moving magnet. If the magnet is moved back and forth repeatedly, the current keeps changing direction. In other words, alternating current (AC) is produced. Alternating current is electric current that keeps reversing direction. Q: What is the term for electric current that keeps reversing direction? Choices: - direct current - AC/DC - magnetic current - alternating current A:
(Answer)
alternating current
Ques: Answer the following question given this paragraph: A space station was established far from the gravitational field of Earth. Extended stays in zero gravity are not healthy for human beings. Thus, for the comfort of the astronauts, the station is rotated so that the astronauts feel there is an internal gravity. The rotation speed is such that the apparent acceleration of gravity is . The direction of rotation is counter-clockwise. If the radius of the station is , what is its rotational speed, ?. Q: Extended stays in zero gravity are not healthy for human beings. thus, for the comfort of the astronauts, the station is rotated so that the astronauts feel there is what? Choices: - revealed gravity - still gravity - Fixed Gravity - internal gravity A:
Ans: internal gravity
(Q).
Answer the following question given this paragraph: The Gaia hypothesis states that the biosphere is its own living organism. The hypothesis suggests that the Earth is self-regulating and tends to achieve a stable state, known as homeostasis . For example the composition of our atmosphere stays fairly consistent, providing the ideal conditions for life. When carbon dioxide levels increase in the atmosphere, plants grow more quickly. As their growth continues, they remove more carbon dioxide from the atmosphere. In this way, the amount of carbon dioxide stays fairly constant without human intervention. Q: What is the hypothesis that states that the biosphere is its own living organism? Choices: - Big Bang theory - Geiger theory - Pascal's hypothesis - gaia hypothesis A:
(A).
gaia hypothesis
Ques:Answer the following question given this paragraph: Lahars are mixtures of ash and water that travel down river valleys. On Mount St. Helens, the eruption melted glaciers. The water mixed with ash from the eruption and created tremendous lahars. The lahars raced down valleys and knocked out many bridges. Q: What do you call mixtures of ash and water that travel down river valleys? Choices: - debris - pollutants - mud slides - lahars A:

Ans:lahars
Ques: Answer the following question given this paragraph: The amount of power passed through transmission lines can be calculated by multiplying voltage by current. The same power can be transmitted using a very high voltage and a very low current as with a low voltage and high current. Q: The amount of power passed through transmission lines can be calculated by multiplying voltage by what? Choices: - resistance - amplification - induction - current A:
Ans:
current