Answer:
As the car travels up the coaster it is gaining potential energy.
Explanation:
Because It has the greatest in amount of potential energy at the top of the coaster. when the car travels down the roller coaster it obtains speed and kinetic energy.
Answer:
Some lenses are used to focus light to a pre-defined point based on the amount of curvature of their surfaces.
In a piano design convex, some surfaces are flat while others has positive lenses (biconvex)
Explanation:
Solution
These lenses are applied to pay attention to light in a point pre-defined based on the amount of curvature of their surfaces.
For that of a plano-convex design, one surface has a positive curve and for biconvex lenses, both surfaces are positively curved while the other remains flat.
when used practically, plano-convex lenses are most commonly used where the object being imaged is far apart from lens.
Answer:

Explanation:
c = Speed of wave
= Density of medium
A = Area
= Frequency

Intensity of sound is given by

So,

We get

The ratio is 
Answer:
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