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.
Choice-a is a very rubbery, imprecise, ambiguous, slippery statement. But it's probably less wrong than any of the other choices on the list.
Explanation:
Let f is the frequency of an oscillation and T is the period of the oscillation. There exists an inverse relationship between the frequency and the time period of the oscillation. Mathematically, it is given by :
Also, 
So,
The time taken to complete one oscillation is called the period of the oscillation and the number of oscillation is called the frequency if an oscillation.
Answer:
This reduces the average force applied during the landing process/ or you can say it reduces the impact your body takes.
Explanation:
The speed of the ball is always zero and the acceleration is always -g when it reaches the top of its motion. This is because when the ball is free, only gravity acts on it which is always downwards, hence g is the net acceleration and it is always negative. However the velocity does not direction change instantly, negative acceleration first slows down the ball with a positive velocity, until that point the ball keeps moving up, then the ball velocity becomes zero just before changing direction and becoming negative after which the ball will now go down along gravity. Hence the ball velocity is zero at the top (neither going up nor down). Mathematically this can be seen as velocity is the integration of acceleration.
