Complete Question
How many turns are in its secondary coil, if its input voltage is 120 V and the primary coil has 210 turns.
The output from the secondary coil is 12 V
Answer:
The value is 
Explanation:
From the equation we are told that
The input voltage is 
The number of turns of the primary coil is 
The output from the secondary is 
From the transformer equation

Here
is the number of turns in the secondary coil
=> 
=>
=>
The frequency at which the body vibrates breaks is natural frequency. The glass with her voice because the frequency of her voice matches the natural frequency of the glass.
<h3>What is the natural frequency?</h3>
When there is no external force acting on the body unless the body vibrates is known as the natural frequency of vibration.it is denoted by
.
when the frequency of a body matches the natural frequency a condition occurs known as resonance.
To learn more about the natural frequency refer to the link;
brainly.com/question/1123932