Answer:
The charge on the dust particle is 
Explanation:
From the question we are told that
The length is 
The width is 
The charge is 
The mass suspended in mid-air is 
Generally the electric field on the carpet is mathematically represented as

Where
is the permittivity of free space with value 
substituting values


Generally the electric force keeping the dust particle on the air equal to the force of gravity acting on the particles

=> 
=> 
=> 
=> 
An object at rest stays at rest and an object in motion<span> stays in </span>motion <span>with the same speed and in the same direction unless acted upon by an unbalanced force.
I hope this helps you </span>
Answer: 12.44 millisecond
Explanation:
Based on the information given, to know the time taken for the impulse, which travels a distance of 1.58m to reach the brain will be:
Time taken = Distance/Speed
Time taken = 1.58/127
Time taken = 0.01244
Time taken = 12.44 millisecond.
The wavelength of the standing wave at fourth harmonic is; λ = 0.985 m and the frequency of the wave at the calculated wavelength is; f = 36.84 Hz
Given Conditions:
mass of string; m = 0.0133 kg
Force on the string; F = 8.89 N
Length of string; L = 1.97 m
1. To find the wavelength at the fourth normal node.
At the fourth harmonic, there will be 2 nodes.
Thus, the wavelength will be;
λ = L/2
λ = 1.97/2
λ = 0.985 m
2. To find the velocity of the wave from the formula;
v = √(F/(m/L)
Plugging in the relevant values gives;
v = √(8.89/(0.0133/1.97)
v = 36.2876 m/s
Now, formula for frequency here is;
f = v/λ
f = 36.2876/0.985
f = 36.84 Hz
Read more about Harmonics of standing waves at; brainly.com/question/10274257
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