The radio is playing at the front of the room. How does the sound get from the speakers to your ears? A: A breeze blows from the speakers and pushes the sound along. B: Vibrations are sent through the air to your ears. C: The sound bounces off a satellite and back to Earth. D: The speakers produce invisible laser beams that carry sound.

Vibrations are sent through the air to your ears.

Explanation:

Sound is a form of energy that is transmitted in compression and rare factions. Sound is a mechanical wave. All mechanical waves require a material medium for propagation.

The material medium for the propagation of sound is air. When the sound is produced by the speakers, the molecules of air are set into vibration and this vibration carries the sound from the speaker to your ears.

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.