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The idea of the electric field, how it's useful, and explains how the electric field is defined.
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Why do astronauts appear weightless despite being near the Earth?
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Basics of gravity and the Law of Universal Gravitation.
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Forces at a distance are explained by fields (gravitational, electric, and magnetic) permeating space that can transfer energy through space. Magnets or electric currents cause magnetic fields; electric charges or changing magnetic fields cause electric fields.
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Magnetism is an interaction that allows certain kinds of objects, which are called ‘magnetic’ objects, to exert forces on each other without physically touching. A magnetic object is surrounded by a magnetic ‘field’ that gets weaker as one moves further away from the object. A second object can feel a magnetic force from the first object because it feels the magnetic field of the first object. The further away the objects are the weaker the magnetic force will be.
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This unit is about how things move along a straight line or, more scientifically, how things move in one dimension. Examples of this would be the movement (motion) of cars along a straight road or of trains along straight railway tracks.
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Speed necessary for the space station to stay in orbit.
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Viewing g as the value of Earth's gravitational field near the surface rather than the acceleration due to gravity near Earth's surface for an object in freefall.
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Introduction to viruses