Answer: The correct answer is True.
Explanation:
Loudness of sound is referred to how soft or loud a sound is for the listener.
This term is measured in a unit known as decibels referred to as dB.
This unit is used to measure the relative intensity of sounds on a scale from zero to 100 dB.
More the value of decibels, it will be uncomfortable for a person to hear that sound.
So Yes, the loudness of sound is measured in decibels.
Explanation:
Given that,
Electrostatic force, 
Distance, 
(a) 
, q is the charge on the ion
(b) Let n is the number of electrons are missing from each ion. It can be calculated as :
n = 2
Hence, this is the required solution.
Answer:
B,D,E
Explanation:
I got you
B. Experiment with a wider range of materials.
D.Use a laboratory galvanometer to make precise measurements.
E. Test the strength of the electromagnet by varying the number of wire coils.
Answer:Reflection
Explanation:
The throwing back of a sound wave without absorbing it is called reflection
In acoustic reflection of sound is termed as echo i.e. sound arrived at the listener after a particular delay depending upon the position of barrier to the observer.
The reflection of sound is used in many devices like megaphone, trumpets, etc. It is also used in auditorium such that the ceiling of the auditorium is curved for multiple reflections of sound so that sound can be reached at every corner of the auditorium.
