85 decibels or higher can cause damage to the human ear.
Decibels is the value of the measurement of sound. Hearing loss can be caused
by noise coming from a loud sound. Noise induced hearing loss maybe permanent
loss or temporary loss. Examples of activities that can give you a noise induced
hearing loss is target shooting, listening to music in your earphones that have
a high volume, and using lawnmowers.
Answer:D.Refractive Indez
Explanation:
It is usually expressed the other way: the ratio of the speed of light in a vacuum to the speed of light in a medium. In that case, it is called the "index of refraction".
Answer:
Height above a surface
Explanation:
Gravitational potential energy is the energy which an object possesses due to its position above a surface.
It is also the amount of work a force has to do in order to bring an object from a particular position to a point of reference.
It is given mathematically as:
P. E. = m*g*h
where m = mass of the body
g = acceleration due to gravity
h = height above a surface
m*g represents the weight of the object.
Hence, Gravitational potential energy is the product of an object's weight and its height above a surface/reference point.
The stroke that begins a point in volleyball is called a serve