Answer:
Option D
Explanation:
The work done can be given by the mechanical energy used to do work, i.e., Kinetic energy and potential energy provided to do the work.
In all the cases, except option D, the energy provided to do the useful work is not zero and hence work done is not zero.
In option D, the box is being pulled with constant velocity, making the acceleration zero and thus Kinetic energy of the system is zero. Hence work done in this case is zero.
The sun always shines directly overhead at noon. This is because the equator always gets the equivalent amount of sunlight. The area always get 12 hours of sunlight, because it's 0 degrees north and south and it's at the center of the Earth.
Answer:
The breaking in <em>molecular</em> bonds in food releases energy for your body to use.
The change in velocity is +4 m/s to the right (or -4 m/s to the left).
The object's mass is irrelevant.
Answer:
ok
Explanation:
The Earth is made of several subsystems or "spheres" that interact to form a complex and continuously changing whole called the Earth system. Scale
Processes operating in the Earth system take place on spatial scales varying from fractions of millimeters to thousands of kilometers, and on time scales that range from milliseconds to billions of years.
Examples of instantaneous - breathing; rotation of the Earth; earthquake
Examples of long term - making coal; plate tectonics
Cycles
The Earth system is characterized by numerous overlapping cycles in which matter is recycled over and over again. Cycles involve multiple spheres and systems interactions.
Examples of cycles: day and night; rock cycle; seasons
Energy
The Earth system is powered by energy from two major sources: the Sun and the planet's internal heat.
Humans and the Earth System
People are part of the Earth system and they impact and are impacted by its materials and processes.
