Answer:
The velocity just before hitting the ground is 
Explanation:
From the question we are told that
The initial speed is 
The final speed is 
From the equations of motion we have that
Where s is the distance travelled which is the height of the cliff
So making it the subject of the the formula we have that
Where a is the acceleration due to gravity with a value 
So
Now we are told that was through horizontally with a speed of
Which implies that this would be its velocity horizontally through out the motion
Now it final velocity vertically can be mathematically evaluated as
Substituting values
The resultant final velocity is mathematically evaluated as
Substituting values
Explanation:
A molecule can be made up from same or different elements. Whereas a compound will have different atoms.
Therefore, the difference between a molecule and a compound is that a compound is made up of atoms from different elements.
For example, 
is a molecule and NaCl is a compound.
And a chemical change creates a new substance.
The bowling ball is at rest, so it only has gravitational potential energy.
Ug = mgy
Ug = (2)(9.8)(40) = 784 J
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Answer:
Waves. Refraction is an effect that occurs when a light wave, incident at an angle away from the normal, passes a boundary from one medium into another in which there is a change in velocity of the light. ... The wavelength decreases as the light enters the medium and the light wave changes direction.
Explanation:
As a wavelength increases in size, its frequency and energy (E) decrease. From these equations you may realize that as the frequency increases, the wavelength gets shorter. ... Mechanical and electromagnetic waves with long wavelengths contain less energy than waves with short wavelengths.
