Answer:
Time = 0.55 s
Height = 8.3 m
Explanation:
The ball is dropped and therefore has an initial velocity of 0. Its acceleration, g, is directed downward in the same direction as its displacement, 
.
The dart is thrown up in which case acceleration, g, acts downward in an opposite direction to its displacement, 
. Both collide after travelling for a time period, t. Let the height of the dart from the ground at collision be and the distance travelled by the ball measured from the top be .
It follows that 
.
Applying the equation of motion to each body (h = v_0t + 0.5at^2),
Ball:
(since 
.)
Dart:
(the acceleration is opposite to the displacement, hence the negative sign)
But
The height of the collision is the height of the dart above the ground, .
Answer:
The answer is "Repetition"
Explanation: when you say something more than 3 times, is called repetiton
It holds the atoms together (aka your last option)
Answer: diffraction
Explanation: reflection wouldn't make sense because it's not reflecting off of anything and same with refraction and absorptions.
Answer:
Mechanical Waves
Explanation:Sound waves in air are longitudinal waves because particles of the medium through which the sound is transported vibrate parallel to the direction that the sound wave moves. A vibrating string can create longitudinal waves.
