The whistling sound from the hearing aids represents that your hearing aids is working perfectly ad is known as the "feedback". So, the given statement is true.
Answer: Option A
<u>Explanation:</u>
It's often sounds irritating when a hearing aids of your grandpa or Grandma whistles. especially, when they put them out of their ears. Actually, this feedback sound from hearing aids occur when the sounds from the outer side bounces back to the microphone of the hearing aids.
The sound bounces back when it doesn't gets inside of your ear canal so that one can hear the sound through the hearing aid. When the sounds bounces back in the hearing aid, it get re-amplified and thus we hear the whistle sound which is known as the feedback of the device.
It's not always the feedback sound though. Sometimes the device whistles when it has some mechanical defect or when one hugs the other one or water gets inside and damaged the whole system.
Answer:
6.1 × 10^9 Nm-1
Explanation:
The electric field is given by
E= Kq/d^2
Where;
K= Coulombs constant = 9.0 × 10^9 C
q = magnitude of charge = 1.62×10−6 C
d = distance of separation = 1.53 mm = 1.55 × 10^-3 m
E= 9.0 × 10^9 × 1.62×10−6/(1.55 × 10^-3 )^2
E= 14.58 × 10^3/2.4 × 10^-6
E= 6.1 × 10^9 Nm-1
the answer is spiral galaxies
So, the time needed before you hear the splash is approximately <u>2.06 s</u>.
<h3>Introduction</h3>
Hi ! In this question, I will help you. This question uses two principles, namely the time for an object to fall freely and the time for sound to propagate through air. When moving in free fall, the time required can be calculated by the following equation:



With the following condition :
- t = interval of the time (s)
- h = height or any other displacement at vertical line (m)
- g = acceleration of the gravity (m/s²)
Meanwhile, for sound propagation (without sound reflection), time propagates is the same as the quotient of distance by time. Or it can be formulated by :

With the following condition :
- t = interval of the time (s)
- s = shift or displacement (m)
- v = velocity (m/s)
<h3>Problem Solving</h3>
We know that :
- h = height or any other displacement at vertical line = 19.6 m
- g = acceleration of the gravity = 9.8 m/s²
- v = velocity = 343 m/s
What was asked :
= ... s
Step by step :
- Find the time when the object falls freely until it hits the water. Save value as





- Find the time when the sound propagate through air. Save value as




- Find the total time




<h3>Conclusion</h3>
So, the time needed before you hear the splash is approximately 2.06 s.
The reason why Lake Jackson disappeared is A. opening of a sinkhole.
Pollution, high atmospheric temperature, and absorption of water by the land aren't enough for an entire lake to disappear, however, a sinkhole may contribute to that. There are two major depressions (sinkholes) in this lake in Florida, and they even have their own names - Porter Sink and Lime Sink.