To solve this problem it is necessary to apply the concepts related to frequency and vibration of strings. Mathematically the frequency can be expressed as

Then the relation between two different frequencies with same wavelength would be


The beat frequency heard when the two strings are sounded simultaneously is



We have the velocity of the transverse waves in stretched string as


And,

Therefore the relation between the two is,


Finally substituting this value at the frequency beat equation we have


Therefore the beats per second are 11.92Hz
In order to determine the acceleration of the block, use the following formula:

Moreover, remind that for an object attached to a spring the magnitude of the force acting over a mass is given by:

Then, you have:

by solving for a, you obtain:

In this case, you have:
k: spring constant = 100N/m
m: mass of the block = 200g = 0.2kg
x: distance related to the equilibrium position = 14cm - 12cm = 2cm = 0.02m
Replace the previous values of the parameters into the expression for a:

Hence, the acceleration of the block is 10 m/s^2
Answer:
a. The station is rotating at 
b. the rotation needed is 
Explanation:
We know that the centripetal acceleration is

where
is the rotational speed and r is the radius. As the centripetal acceleration is feel like an centrifugal acceleration in the rotating frame of reference (be careful, as the rotating frame of reference is <u>NOT INERTIAL,</u> the centrifugal force is a fictitious force, the real force is the centripetal).
<h3>a. </h3>
The rotational speed is :




Knowing that there are
in a revolution and 60 seconds in a minute.


<h3>b. </h3>
The rotational speed needed is :




Knowing that there are
in a revolution and 60 seconds in a minute.


The answer to your question is Speed
To solve this problem it is necessary to apply the concepts related to mutual inductance in a solenoid.
This definition is described in the following equation as,

Where,
permeability of free space
Number of turns in solenoid 1
Number of turns in solenoid 2
Cross sectional area of solenoid
l = Length of the solenoid
Part A )
Our values are given as,





Substituting,



PART B) Considering that many of the variables remain unchanged in the second solenoid, such as the increase in the radius or magnetic field, we can conclude that mutual inducantia will appear the same.